CAS-005 CompTIA SecurityX Certification Exam Question and Answers

Analysis and Remediation Options for Each IoC:

IoC 1:

Evidence:

Source: Apache_httpd

Type: DNSQ

Dest: @10.1.1.1:53,@10.1.2.5

Data: update.s.domain, CNAME 3a129sk219r9slmfkzzz000.s.domain, 108.158.253.253

Analysis:

Analysis: The service is attempting to resolve a malicious domain.

Reason: The DNS queries and the nature of the CNAME resolution indicate that the service is trying to resolve potentially harmful domains, which is a common tactic used by malware to connect to command-and-control servers.

Remediation:

Remediation: Implement a blocklist for known malicious ports.

Reason: Blocking known malicious domains at the DNS level prevents the resolution of harmful domains, thereby protecting the network from potential connections to malicious servers.

IoC 2:

Evidence:

Src: 10.0.5.5

Dst: 10.1.2.1, 10.1.2.2, 10.1.2.3, 10.1.2.4, 10.1.2.5

Proto: IP_ICMP

Data: ECHO

Action: Drop

Analysis:

Analysis: Someone is footprinting a network subnet.

Reason: The repeated ICMP ECHO requests to different addresses within a subnet indicate that someone is scanning the network to discover active hosts, a common reconnaissance technique used by attackers.

Remediation:

Remediation: Block ping requests across the WAN interface.

Reason: Blocking ICMP ECHO requests on the WAN interface can prevent attackers from using ping sweeps to gather information about the network topology and active devices.

IoC 3:

Evidence:

Proxylog:

GET /announce?info_hash=%01dff%27f%21%10%c5%wp%4e%1d%6f%63%3c%49%6d&peer_id%3dxJFS

Uploaded=0&downloaded=0&left=3767869&compact=1&ip=10.5.1.26&event=started

User-Agent: RAZA 2.1.0.0

Host: localhost

Connection: Keep-Alive

HTTP200 OK

Analysis:

Analysis: An employee is using P2P services to download files.

Reason: The HTTP GET request with parameters related to a BitTorrent client indicates that the employee is using peer-to-peer (P2P) services, which can lead to unauthorized data transfer and potential security risks.

Remediation:

Remediation: Enforce endpoint controls on third-party software installations.

Reason: By enforcing strict endpoint controls, you can prevent the installation and use of unauthorized software, such as P2P clients, thereby mitigating the risk of data leaks and other security threats associated with such applications.

Encrypting patient data at rest ensures that sensitive information is protected from unauthorized access, thereby maintaining patient privacy. Additionally, encryption supports data portability by allowing secure transfer and storage of data across different systems and devices without compromising confidentiality. This practice is crucial for healthcare providers to comply with regulations such as the Health Insurance Portability and Accountability Act (HIPAA), which mandates the protection of patient information.​

Theregulated lab environment (Yes)shares the same VLAN (10.2.0.0/22) withusers, creatingzone traversalrisk from unregulated zones to sensitive datanetworks.

This allows pivoting and lateral movement from non-regulated user devices into regulated lab environments — a classiczone boundary violation.

Zone traversal should be mitigated with segmentation and firewall enforcement.

FromCAS-005, Domain 2: Risk Management and Mitigation Strategies:

“Zone traversal occurs when segmentation boundaries are misconfigured or merged, leading to regulatory and risk compliance failures.”

OpenSSH vulnerabilityispublic facingand has acritical CVSS of 9.2.

Exploitable SSH services can lead to direct server compromise.

Although Apache has a higher score, it's internal.

FromCAS-005, Domain 3: Vulnerability Management:

“Prioritize external vulnerabilities with high CVSS and exposed attack surfaces.”

The SIEM already contains multiple events that, if correlated, would have indicated an active attack sequence on VM001—such as denied connections, IPS alerts, malware detection, and then an allowed connection. CAS-005 Security Operations objectives emphasize log correlation as a way to enhance detection by linking related events across different time stamps and data sources into a single, higher-confidence alert.

Option A (adding EDR logs) could add visibility but does not address the need to connect existing events for earlier detection.

Option C (improving parsing) ensures readability but does not create actionable alerts.

Option D (creating a new malware detection rule) is redundant since malware detection already appeared in logs; the issue was the lack of correlation to act on it in time.

By correlating IDS, IPS, firewall, and malware detection logs, the SIEM can raise a higher-priority alert before the attack is completed.

For a disaster recovery (DR) plan requiring immediate data availability, the first step is understanding what needs to be protected and recovered. Identifying critical business processes and their associated software and hardware requirements establishes the foundation for the DR plan. This ensures that backups and recovery mechanisms align with business priorities, meeting the "moment's notice" requirement.

Option A:A change management plan is important for system consistency but doesn’t directly address immediate data availability in a DR context.

Option B:Hiring staff supports execution but doesn’t define what needs to be recovered or how. It’s a later step.

Option C:A warm site (a partially operational backup site) is a good DR solution, but designing it comes after identifying critical processes and resources.

Option D:This is the first step in any DR planning process—knowing what’s critical ensures the plan meets availability goals efficiently.

Public Key Infrastructure (PKI) supports change management by securing messages (e.g., approvals, updates).Non-repudiation, provided via digital signatures, ensures a sender cannot deny sending a message, critical for auditability in change processes.

Option A:Correct—PKI’s digital signatures ensure non-repudiation.

Option B:Confidentiality (via encryption) is a PKI feature but less tied to change management’s focus on accountability.

Option C:Delivery receipts are not aPKI function; they’re protocol-specific (e.g., SMTP).

Option D:Attestation relates to verifying attributes, not a direct PKI message capability.

Implementing digital signatures ensures the integrity and authenticity of software binaries. When a binary is digitally signed, any tampering with the file (e.g., replacing it with amalicious version) would invalidate the signature. This allows systems to verify the origin and integrity of binaries before execution, preventing the execution of unauthorized or compromised binaries.

A. Improving patching processes: While important, this does not directly address the issue of verifying the integrity of binaries.

B. Implementing digital signatures: This ensures that only valid, untampered binaries are executed, preventing attackers from substituting legitimate binaries with malicious ones.

C. Performing manual updates via USB ports: This is not practical and does not scale well, especially in large environments.

D. Allowing only files from internal sources: This reduces the risk but does not provide a mechanism to verify the integrity of binaries.

Managing telemetry and differentiating it by office requires a way to categorize data. Let’s evaluate:

A. Sensor placement:Useful for data collection but doesn’t inherently differentiate by office.

B. Data labeling:Assigns metadata (e.g., office location) to telemetry, enabling differentiation. This aligns with CAS-005’s focus on data management for security operations.

C. Continuous monitoring:Ensures ongoing data collection but doesn’t address differentiation.

The sshd_config file is the main configuration file for the OpenSSH server. To disable weak CBC (Cipher Block Chaining) ciphers for SSH connections, the security engineer should modify the sshd_config file to update the list of allowed ciphers. This file typically contains settings for the SSH daemon, including which encryption algorithms are allowed.

By editing the /etc/ssh/sshd_config file and updating the Ciphers directive, weak ciphers can be removed, and only strong ciphers can be allowed. This change ensures that the SSH server does not use insecure encryption methods.

The output indicates that the software tool contains hard-coded credentials, which attackers can exploit to bypass user access controls and load the database. The mostlikely recommendation is to remove hard-coded credentials from the source code. Here’s why:

Security Best Practices: Hard-coded credentials are a significant security risk because they can be easily discovered through reverse engineering or simple inspection of the code. Removing them reduces the risk of unauthorized access.

Credential Management: Credentials should be managed securely using environment variables, secure vaults, or configuration management tools that provide encryption and access controls.

Mitigation of Exploits: By eliminating hard-coded credentials, the organization can prevent attackers from easily bypassing authentication mechanisms and gaining unauthorized access to sensitive systems.

In a federated environment divided by region, if user identities are not synchronized across regions, authentication may be slow or fail when employees travel. CAS-005 IAM guidance states that identity synchronization ensures user attributes and credentials are consistently available in all regions, reducing latency and login issues.

Option A creates separate identities, which breaks single identity management.

Option C is unrelated to the login performance issue.

Option D may resolve SSO appliance sync but not cross-region identity data availability.

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The event timeline indicates a sequence where a file (hr-reporting.docx) was saved, scanned, executed, and eventually found to contain malware. The critical issue here is that the malware scan completed after the file was already executed. This suggests a Time-Of-Check to Time-Of-Use (TOCTOU) vulnerability, where the state of the file changed between the time it was checked and the time it was used.

Step by Step Explanation:

Understanding the Scenario: The question focuses on the historical design assumptions behind older operational technology (OT)systems, particularly in the context of command, control, and telemetry.

Analyzing the Answer Choices:

A. operating in an isolated/disconnected system: This is the most accurate assumption for many legacy OT systems. Historically, these systems weredesigned to operate in air-gapped environments, completely isolated from external networks (including the internet).

The most likely explanation for the issues encountered with the captive portal is that the TLS ciphers supported by the captive portal are deprecated. Here’s why:

TLS Cipher Suites: Modern browsers are continuously updated to support the latest security standards and often drop support for deprecated and insecure cipher suites. If the captive portal uses outdated TLS ciphers, newer browsers may refuse to connect, causing security errors.

HSTS and Browser Security: Browsers with HTTP Strict Transport Security (HSTS) enabled will not allow connections to sites with weak security configurations. Deprecated TLS ciphers would cause these browsers to block the connection.

Comprehensive and Detailed Explanation:

SecurityX CAS-005 emphasizes automation with validation in security operations. Security Orchestration, Automation, and Response (SOAR) platforms can integrate with Threat Intelligence Platforms (TIPs) to verify threat indicators before triggering automated endpoint isolation through EDR APIs. This approach reduces the spread of malware while minimizing the chance of isolating clean systems due to false positives.

Isolating endpoints on any alert (B) is high-risk and can disrupt business operations.

Manual review (C) is too slow for fast-moving threats.

Suppressing alerts (D) risks missing critical events entirely.

Comprehensive and Detailed Explanation:

Always-on VPN ensures that devices connect automatically to the corporate network whenever they are online, allowing seamless access to internal resources and enabling authentication against on-premises directory services (such as Active Directory). This supports centralized identity management, GPO enforcement, and compliance requirements.

Options B, C, and D involve local or peripheral resources, which are unaffected by VPN state.

Comprehensive and Detailed Explanation:

According to SecurityX CAS-005 threat intelligence and testing objectives, a honeypot is a decoy system designed to lure attackers, allowing security teams to observe new tactics, techniques, and procedures (TTPs) in a controlled environment.

An IPS is designed to block known attacks but not discover new ones.

Sandboxing is useful for analyzing suspicious files or malware samples but not for attracting live, unknown attack attempts.

Scanning for IoCs detects known compromise indicators, not new, emerging attacks.A honeypot directly supports proactive attack discovery and analysis.

This scenario describes anenterprise VPN setup that requires machine authenticationbefore a user logs in. The best explanation for this requirement is that theVPN client selects the appropriate certificate automaticallybased on the key extension in the machine certificate.

Understanding the Key Extension Requirement:

PKI (Public Key Infrastructure)issues machine certificates that include specific key usages such asClient AuthenticationorIPSec IKE Intermediate.

Key usage extensionsdefine how a certificate can be used, ensuring that onlyvalid certificates are selected by the VPN client.

Why Option B is Correct:

The VPNautomaticallyselects the correct machine certificate with the appropriate key extension.

The process occurswithout user intervention, ensuring seamless VPN authentication before login.

Why Other Options Are Incorrect:

A (MFA requirement):Certificates used in this scenario are for machine authentication, not user MFA. MFA typically involves user credentials plus a second factor (like OTPs or biometrics), which isnot applicable here.

C (Wi-Fi connectivity before login):This refers topre-logon networking, which is a separate concept where devices authenticate to a Wi-Fi network before login, usually via 802.1X EAP-TLS. However, this question specifically mentions VPN authentication, not Wi-Fi authentication.

D (SSL VPN with certificates):While SSL VPNs do use certificates,this scenario involves machine certificates issued by an internal PKI, which are commonly used inIPSec VPNs, not SSL VPNs.

The log shows an AXFR (zone transfer) query, which exposed internal DNS records, aiding lateral movement. Let’s evaluate:

A. Disabling DNS zone transfers:AXFR allows full DNS zone data to be transferred. Disabling it externally prevents attackers from mapping internal networks, directly mitigating this issue per CAS-005’s security operations focus.

B. Restricting to UDP/53:AXFR uses TCP/53, so this wouldn’t stop it.

C. DNSmasking:Obscures records but isn’t a standard term for this fix.

Integrating IDS, firewall, and DLP to reduce response time requires orchestration and automation. Let’s evaluate:

A. SOAR(Security Orchestration, Automation, and Response):SOAR integrates security tools, automates workflows, and speeds up incident response. It’s the best fit for this scenario, as CAS-005 highlights SOAR for operational efficiency.

B. CWPP (CloudWorkload Protection Platform):Focused on securing cloud workloads, not integrating on-premises tools.

C. XCCDF (Extensible Configuration Checklist Description Format):A standard for compliance checklists, not a tool for integration or response.

A proxy-based Cloud Access Security Broker (CASB) is chosen primarily for its ability to block unapproved applications and services. Here’s why:

Application and Service Control: Proxy-based CASBs can monitor and control the use of applications and services by inspecting traffic as it passes through the proxy. This allows the organization to enforce policies that block unapproved applications and services, ensuring compliance with security policies.

Visibility and Monitoring: By routing traffic through the proxy, the CASB can provide detailed visibility into user activities and data flows, enabling better monitoring and threat detection.

Real-Time Protection: Proxy-based CASBs can provide real-time protection against threats by analyzing and controlling traffic before it reaches the end user, thus preventing the use of risky applications and services.

The Common Vulnerability Scoring System (CVSS) v3.1 uses three metric groups to calculate overall scores:Base,Temporal, andEnvironmental.

Base (E):Mandatory metrics assessing exploitability (e.g., attack vector) and impact (confidentiality, integrity, availability).

Temporal (A):Optional metrics reflecting the current state of the vulnerability (e.g., exploit availability, remediation level).

Environmental (F):Optional metrics tailoring the score to the organization’s context (e.g., security requirements).

B, C, D (Availability, Integrity, Confidentiality):These are subcomponents of the Base Impact metrics, not standalone groups.

G (Impact):A categorywithin Base, not a group.

H (Attack vector):A single Base metric, not a group.

Based on the security policy that any publicly available server must be patched within 12 hours after a patch is released, the securityanalyst should patch Host 1 first. Here’s why:

Public Availability: Host 1 is externally available, making it accessible from the internet. Publicly available servers are at higher risk of being targeted by attackers, especially when a zero-day vulnerability is known.

Exposure to Threats: Host 1 has IIS installed and is publicly accessible, increasing its exposure to potential exploitation. Patching this host first reduces the risk of a successful attack.

Prioritization of Critical Assets: According to best practices, assets that are exposed to higher risks should be prioritized for patching to mitigate potential threats promptly.

The table shows detailed information about products, includinglocation, chassis manufacturer, OS, application developer, and vendor. This type of information is typically assessed in a supply chain assessment to evaluate the security and reliability of components and services from different suppliers.

Why Supply Chain Assessment?

Component Evaluation: Assessing the origin and security of each component used in the products, including hardware, software, and third-party services.

Vendor Reliability: Evaluating the security practices and reliability of vendors involved in providing components or services.

Risk Management: Identifying potential risks associated with the supply chain, such as vulnerabilities in third-party components or insecure development practices.

Other types of assessments do not align with the detailed supplier and component information provided:

A. System: Focuses on individual system security, not the broader supply chain.

C. Quantitative: Focuses on numerical risk assessments, not supplier information.

D. Organizational: Focuses on internal organizational practices, not external suppliers.

Understanding the Security Event:

HOST002 is the only device authorized for internet traffic. However, theSIEM logs show that VM002 is making network connections to web.corp.local.

This indicatesunauthorized access, which could bea sign of lateral movement or network infection.

This is ared flagfor potential malware, unauthorized software, or a compromised host.

Why Option D is Correct:

Unusual network traffic patternsare often an indicator of acompromised system.

VM002 should not be communicating externally, but it is.

This suggests a possiblebreach or malware infectionattempting to communicate with a command-and-control (C2) server.

Why Other Options Are Incorrect:

A (Misconfiguration):While a misconfiguration could explain the unauthorized connections, the pattern of activity suggests something more malicious.

B (Security incident on HOST002):The issue is not with HOST002. The suspicious activity isfrom VM002.

C (False positives):The repeated pattern of unauthorized connections makes false positivesunlikely.

In the context of establishing a Security Operations Center (SOC) with a threat-modeling function, it's crucial to understand how data flows within the organization's systems. Network and data flow diagrams provide a visual representation of the system's architecture, illustrating how data moves between components, which is essential for identifying potential security weaknesses and antipatterns. Antipatterns are common responses to recurring problems that are ineffective and risk-inducing. By analyzing these diagrams, the consultant can pinpoint areas where security controls may be lacking or misconfigured, thereby facilitating the development of effective threat models.​

While other options like unpatchable IoT devices (Option B) and inventories of cloud resources (Option E) are important for comprehensive security assessments, they are more pertinent during later stages, such as vulnerability management and asset inventory. The initial phase of threat modeling focuses on understanding the system's structure and data flows to identify potential threats, making network and data flow diagrams the most critical information at this stage.​

Matching Relevant Findings to the Affected Hosts:

Finding 1:

Affected Host: DNS

Reason: Users are unable to log into the domain from their workstations after relocating to Site B, which implies a failure in domain name services that are critical for user authentication and domain login.

Finding 2:

Affected Host: Pumps

Reason: Thepump room at Site B becoming inoperable directly points to the critical infrastructure components associated with pumping operations.

Finding 3:

Affected Host: VPN Concentrator

Reason: Unreliable internet connectivity at Site B due to route flapping indicates issues with network routing, which is often managed by VPN concentrators that handle site-to-site connectivity.

Corrective Actions for Finding 3:

Finding 3 Corrective Action:

Action: Modify the BGP configuration

Reason: Route flapping is often related to issues with Border Gateway Protocol (BGP) configurations. Adjusting BGP settings can stabilize routes and improve internet connectivity reliability.

Replication to Site B for Finding 1:

Affected Host: DNS

Domain Name System (DNS) services are essential for translating domain names into IP addresses, allowing users to log into the network. Replicating DNS services ensures that even if Site A is disrupted, users at Site B can still authenticate and access necessary resources.

Replication to Site B for Finding 2:

Affected Host: Pumps

The operation of the pump room is crucial for maintaining various functions within the infrastructure. Replicating the control systems and configurations for the pumps at Site B ensures that operations can continue smoothly even if Site A is affected.

Configuration Changes for Finding 3:

Affected Host: VPN Concentrator

Route flapping is a situation where routes become unstable, causing frequent changes in the best path for data to travel. This instability can be mitigated by modifying BGP configurations to ensure more stable routing. VPN concentrators, which manage connections between sites, are typically configured with BGP for optimal routing.

Configuring a span port on the perimeter firewall to ingest logs is the best architectural change to ensure that all client proxy traffic is captured for analysis. Here’s why:

Comprehensive Traffic Capture: A span port (or mirror port) on the perimeter firewall can capture all inbound and outbound traffic, including traffic that might bypass the proxy. This ensures that all network traffic is available for analysis.

Centralized Logging: By capturing logs at the perimeter firewall, the organization can centralize logging and analysis, making it easier to detect and investigate anomalies.

Minimal Disruption: Implementing a span port is a non-intrusive method that does not require significant changes to the network architecture, thus minimizing disruption to existing services.

Privileged Access Management (PAM)restricts elevated permissions, reducing the risk of widespread ransomware attacks.Multi-Factor Authentication (MFA)protects against credential theft and ensures that even if passwords are compromised, accounts are not easily accessible.Network segmentationbreaks the flat network into secure zones, limiting lateral movement by attackers. SD-WAN and BGP relate to network routing and efficiency, not security architecture specifically. Remote access VPN secures external access but does not solve internal flat network issues. Network Access Control (NAC) is helpful but secondary compared to PAM, MFA, and segmentation in this context.

The security engineer should modify the following to fix the email migration issues:

Email CNAME Record: The email CNAME record must be changed to a type A record pointing to 192.168.1.10. This is because CNAME records should not be used where an IP address (A record) is required. Changing it to an A record ensures direct pointing to the correct IP.

TXT Record for DMARC: The TXT record must be changed to "v=dmarc ip4:192.168.1.10 include

com -all". This ensures proper configuration of DMARC (Domain-based Message Authentication, Reporting & Conformance) to include the correct IP address and the email service provider domain.

DMARC: Ensuring the DMARC record is correctly set up helps in preventing email spoofing and phishing, aligning with email security best practices.

Device attestationensures that only corporate-approved devices can perform privileged actions in SaaS applications.Continuous authorizationmonitors ongoing device compliance, dynamically adjusting permissions based onsecurity posture.

Blocking connections (A)is too restrictive and does not accommodate BYOD.

Machine certificates (B)help with authentication but do not provide continuous security assessment.

MDM policies (D)secure mobile devices but do not apply real-time access controls for SaaS applications.

To determine how the acquisition of Company B will impact the attack surface, the following steps are crucial:

A. Documenting third-party connections used by Company B: Understanding all external connections is essential for assessing potential entry points for attackers and ensuring that these connections are secure.

E. Performing an architectural review of Company B's network: This review will identify vulnerabilities and assess the security posture of the acquired company's network, providing a comprehensive understanding of the new attack surface.

These actions will provide a clear picture of the security implications of the acquisition and help in developing a plan to mitigate any identified risks.

Chain of custody ensures that evidence is protected, documented, and accounted for from the moment it is collected until it is presented in court or a legal proceeding. Properly maintaining chain of custody is critical to proving that the evidence has not been tampered with. Although encryption protects data during transit, and legal issues are important, without a documented chain of custody, the integrity of the evidence itself could be challenged and invalidated.

The hijacked administrator account was used across multiple ASNs (indicating different network locations) in a short time, despite MFA and SSO. This suggests a stolen session or token misuse. Let’s analyze:

A. Token theft detection with lockouts:Useful for detecting stolen SSO tokens, but it’s reactive and may not prevent initial misuse across networks.

B. Context-based authentication:This adds real-time checks (e.g., geolocation, IP changes) to verify login attempts. Given the rapid ASN changes, this proactively mitigates the issue by challenging suspicious logins, aligning with CAS-005’s focus on adaptive security.

C. Decentralize accounts:This removes SSO, increasing complexity and weakening MFA enforcement, which isn’t practical or secure.

VPN Concentrator:

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AAA Server:

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The logs indicate unauthorized access from104.18.16.29, an external IP, to the building camera’s administrative console during off-hours.Restricting access only to approved IPsensures that only authorized personnel can remotely control the cameras, reducing the risk of unauthorized access and manipulation.

Implementing WAF protection (A)secures against web application attacks but does not restrict unauthorized administrative access.

Upgrading the firmware (B)is good security hygiene but does not immediately mitigate the active threat.

Blocking IP 104.18.16.29 (D)is a temporary measure, as an attacker can switch to another IP. A better long-term solution is whitelisting trusted IPs.

Step-by-Step Explanation:

Both samples share similar function names, variable naming styles, and logic flow, indicating that they were likely written by the same developer. This is a keyobservation in malware attribution, as cyber threat analysts often look for unique coding styles to link malware to specific threat actors.

The presence of C2 (Command and Control) communication in both samples supports this theory, as attackers often reuse parts of their own malware code across different attacks.

Comprehensive and Detailed Explanation:

Code signing uses cryptographic digital signatures to prove that software or updates come from a trusted source and have not been altered. In the SecurityX CAS-005 objectives, this is covered under security engineering and cryptographic assurance mechanisms.

Envelope encryption protects confidentiality but does not authenticate the source.

File integrity monitoring detects file changes but does not confirm the origin of the update.

Application control manages which software can run but does not ensure authenticity of distributed files.Only code signing meets all three objectives: verifying the source, ensuring authorization, and proving integrity.

Context-based authentication enhances traditional security methods by incorporating additional layers of information about the user's current environment and behavior. This can include factors such as the user's location, the time of access, the device used, and the behavior patterns. It is particularly useful in preventing unauthorized access even if an attacker has obtained a valid password.

Rule-based (A) focuses on predefined rules and is less flexible in adapting to dynamic threats.

Time-based (B) authentication considers the time factor but doesn't provide comprehensive protection against stolen credentials.

Role-based (C) is more about access control based on the user's role within the organization rather than authenticating the user based on current context.

By implementing context-based authentication, the company can ensure that even if a password is compromised, the additional contextual factors required for access (which an attacker is unlikely to possess) provide a robust defense mechanism.

Advancements in quantum computing pose a significant threat to current encryption systems, especially those based on the difficulty of factoring large prime numbers, such as RSA. Quantum computers have the potential to solve these problems exponentially faster than classical computers, making current cryptographic systems vulnerable.

Why Large Prime Numbers are Vulnerable:

Shor's Algorithm: Quantum computers can use Shor's algorithm to factorize large integers efficiently, which undermines the security of RSA encryption.

Cryptographic Breakthrough: The ability to quickly factor large prime numbers means that encrypted data, which relies on the hardness of thismathematical problem, can be decrypted.

Other options, while relevant, do not capture the primary reason for the shift towards new encryption algorithms:

B. Zero Trust security architectures: While important, the shift to homomorphic encryption is not the main driver for new encryption algorithms.

C. Perfect forward secrecy: It enhances security but is not the main reason for new encryption algorithms.

D. Real-time IP traffic capture: Quantum computers pose a more significant threat to the underlying cryptographic algorithms than to the real-time capture of traffic.

This scenario describes an attack where the attacker mimics the CEO’s voice to deceive the CFO, likely using AI-generated audio. According to the CompTIA SecurityX CAS-005 study guide (Domain 1: Security Strategy and Risk Management, 1.2), a deepfake attack involves using artificial intelligence to create realistic but fake audio, video, or other media to impersonate someone. In this case, the voice similarity suggests a deepfake audio attack, which is a targeted social engineering tactic.

Option A:Smishing involves SMS-based phishing, not voicecalls.

Option C:Automated exploit generation refers to creating software exploits, not impersonation.

Option D:Spear phishing targets specific individuals but typically via email, not voice-based impersonation.

Option B:Deepfake is the most accurate, as it describes AI-driven impersonation of the CEO’s voice.

To meet the requirements of only allowing internally signed applications, preventing unauthorized software installations, and logging attempts to run unauthorized software, configuring application control with blocked hashes and enterprise-trusted root certificates is the best solution. This approach ensures that only applications signed by trusted certificates are allowed to execute, while all other attempts are blocked and logged. It effectively prevents unauthorized software installations by restrictingexecution to pre-approved applications.

In serverless computing, organizations rely heavily on CSPs to manage the infrastructure, runtime, and scaling. A key risk is thelevel of control and influence governments have over CSPs, potentially affecting availability, access, or confidentiality of hosted services due to legal orders or government actions. Concerns about virtualization technologies, scalability, or third-party monitoring are valid but less critical compared to the overarching legal and control risks tied to CSP reliance.

Investing in a threat intelligence platform is the best option for a company looking to operationalize research output. A threat intelligence platform helps in collecting, processing, and analyzing threat data to provide actionable insights. These platforms integrate data from various sources, including dark web monitoring, honeypots, and other security tools, to offer a comprehensive view of the threat landscape.

Why a Threat Intelligence Platform?

Data Integration: It consolidates data from multiple sources, including dark web monitoring and honeypots, making it easier to analyze and derive actionableinsights.

Actionable Insights: Provides real-time alerts and reports on potential threats, helping the organization take proactive measures.

Operational Efficiency: Streamlines the process of threat detection and response, allowing the security team to focus on critical issues.

Research and Development: Facilitates the operationalization of research output by providing a platform for continuous monitoring and analysis of emerging threats.

Other options, while valuable, do not offer the same level of integration and operationalization capabilities:

A. Dark web monitoring: Useful for specific threat intelligence but lacks comprehensive operationalization.

C. Honeypots: Effective for detecting and analyzing specific attack vectors but not for broader threat intelligence.

D. Continuous adversary emulation: Important for testing defenses but not for integrating and operationalizing threat intelligence.

To ensure always-on VPN access is enabled and restricted to company assets, the network engineer needs to generate device certificates using the specific template settings required for the company's VPN solution. These certificates ensure that only authorized devices can establish a VPN connection.

Why Device Certificates are Necessary:

Authentication: Device certificates authenticate company assets, ensuring that only authorized devices can access the VPN.

Security: Certificates provide a higher level of security compared to username and password combinations, reducing the risk of unauthorized access.

Compliance: Certificates help in meeting security policies and compliance requirements by ensuring that only managed devices can connect to the corporate network.

Other options do not provide the same level of control and security for always-on VPN access:

B. Modify signing certificates for IKE version 2: While important for VPN protocols, it does not address device-specific authentication.

C. Create a wildcard certificate: This is not suitable for device-specific authentication and could introduce security risks.

D. Add the VPN hostname as a SAN entry: This is more related to certificate management and does not ensure device-specific authentication.

To reduce the risk of unauthorized BYOD (Bring Your Own Device) usage, the organization should implement Conditional Access and Network Access Control (NAC).

Why Conditional Access and NAC?

Conditional Access:

User-to-Device Binding: Conditional access policies can enforce that only registered and compliant devices are allowed to access corporate resources.

Context-Aware Security: Enforces access controls based on the context of the access attempt, such as user identity, device compliance, location, and more.

Network Access Control (NAC):

DeviceConfiguration Requirements: NAC ensures that only devices meeting specific security configurations are allowed to connect to the network.

Access Control: Provides granular control over network access, ensuring that BYOD devices comply with security policies before gaining access.

Other options, while useful, do not address the specific need to control and secure BYOD devices effectively:

A. Cloud IAM to enforce token-based MFA: Enhances authentication security but does not control device compliance.

D. PAM to enforce local password policies: Focuses on privileged account management, not BYOD control.

E. SD-WAN to enforce web content filtering: Enhances network performance and security but does not enforce BYOD device compliance.

F. DLP to enforce data protection capabilities: Protects data but does not control BYOD device access and compliance.

To protect company information on stolen mobile devices, implementingremote wipe proceduresensures data can be erased if a device is suspected lost or stolen.Biometric access controlwith enforced timeouts further secures the device, requiring biometric authentication periodically, thus limiting unauthorized access even if the device is stolen. Geofencing and certificates provide additional security layers but are less immediate protections against information exposure after theft. Application control and side-loading prevention are important for malware threats but less so for stolen device scenarios.

The issue is tracing the original source of requests in a tiered architecture with a load balancer. The web server logs show internal IPs (192.168.1.10), not the external client IPs, because the load balancer forwards requests without preserving the source. Enabling theX-Forwarded-Forheader on the load balancer adds the client’s original IP to the HTTP request headers, allowing downstream servers to log it. This ensures traceability without altering the architecture significantly.

Option A:Correct—X-Forwarded-For is the standard solution for preserving client IPs through load balancers.

Option B:A Host-based Intrusion Detection System (HIDS) detects anomalies but doesn’t address IP traceability.

Option C:A trusted CA certificate fixes the self-signed warning but is unrelated to source tracking.

Option D:Stored procedures improve database security but don’t help with IP logging.

Option E:Storing $_SERVER['REMOTE_ADDR'] captures the loadbalancer’s IP, not the client’s, unless X-Forwarded-For is enabled.

The question states that security scanning and quality assurance (QA) in the CI/CD pipeline have been completed with no issues, indicating that the code in the test branch is ready for production. According to the CompTIA SecurityX CAS-005 study guide (Domain 2: Security Operations, 2.3), in a secure CI/CD pipeline, once code passes automated security scans, QA, and other checks (e.g., unit testing, peer reviews), the next step is to merge the tested branch into the main branch for deployment to production.

Option B:Threat modeling is typically performed earlier, during design or development, not after passing CI/CD checks.

Option C:Unit testing is part of the CI/CD pipeline and should already be completed.

Option D:Peer reviews are conducted before or during the test phase, not after QAand security scans are clear.

Option A:Merging the test branch to the main branch is the logical next step to prepare for production deployment.

Comprehensive and Detailed Explanation:

In a Discretionary Access Control (DAC) model, the data owner or an assigned stakeholder has the authority to determine who can access resources. SecurityX CAS-005 IAM objectives describe DAC as user- or owner-controlled, where permissions can be granted or revoked at the owner’s discretion.

In this scenario, because permissions from the legacy system could not be migrated, multiple stakeholders were made responsible for assigning and managing access—matching the DAC model’s characteristics.

Option A relates to outsourcing, which does not define an access control model.

Option C is about authentication limitations, unrelated to the choice of DAC.

Option D describes backup responsibilities, which are operational tasks, not access control.

Forward secrecy (FS) ensures that past encrypted data remains secure even if encryption keys are compromised in the future. Itgenerates ephemeral session keys that are not reused.

Other options:

A (Tokenization) replaces sensitive data with tokens but does not prevent key compromise.

B (Key stretching) makes brute-force attacks harder but does not ensure secrecy after compromise.

D (Simultaneous Authentication of Equals – SAE) is used in WPA3 but is not related to past communication security.

This scenario clearly describes asupply chain attack, where the compromise occurs at the vendor or manufacturing stage before the product reaches the customer. The attack impacts many downstream organizations and sectors. SDLC attacks are focused on software development life cycles, side-loading involves unauthorized app installations, and remote code signing focuses on authenticating remote software, none of which fully encapsulate the situation described.

The technique that best addresses the issue of insider threats from employees who have individual access to encrypted material is key splitting. Here’s why:

Key Splitting: Key splitting involves dividing a cryptographic key into multiple parts anddistributing these parts among different individuals or systems. This ensures that no single individual has complete access to the key, thereby mitigating the risk of insider threats.

Increased Security: By requiring multiple parties to combine their key parts to access encrypted material, key splitting provides an additional layer of security. This approach is particularly useful in environments where sensitive data needs to be protected from unauthorized access by insiders.

Compliance and Best Practices: Key splitting aligns with best practices and regulatory requirements for handling sensitive information, ensuring that access is tightly controlled and monitored.

Vendor lock-in occurs when a client is overly dependent on a vendor, limiting flexibility. Risks include:

Option B:Vendors changing offerings (e.g., features, pricing) can disrupt the client, a key lock-in risk.

Option D:Decreased quality of service may result from reliance on a single vendor without alternatives.

Option A:Seamless data movement is a benefit, not a risk.

Option C:Sufficient service is neutral or positive, not a risk.

Option E:Multicloud is hindered by lock-in, not a risk of it.

Option F:Increased interoperability contradicts lock-in’s limitations.

The best location to test a newly released feature for an internal application, without affecting the production environment, is the staging environment. Here’s a detailed explanation:

Staging Environment: This environment closely mirrors the production environment in terms of hardware, software, configurations, and settings. It serves as a final testing ground before deploying changes to production. Testing in the staging environment ensures that the new feature will behave as expected in the actual production setup.

Isolation fromProduction: The staging environment is isolated from production, which means any issues arising from the new feature will not impact the live users or the integrity of the production data. This aligns with best practices in change management and risk mitigation.

Realistic Testing: Since the staging environment replicates the production environment, it provides realistic testing conditions. This helps in identifying potential issues that might not be apparent in a development or testing environment, which often have different configurations and workloads.

Step by Step Explanation:

Understanding the Scenario: The question is about ensuring that an organization retains control over its encryption keys. It focuses on different key storage and management methods.

Analyzing the Answer Choices:

A. Encrypting using a key stored in an on-premises hardware security module (HSM): This is thebest option for maintaining complete control over encryption keys. An HSM is a dedicated, tamper-resistant hardware device specifically designed for secure key storage and cryptographic operations. Storing keys on-premises within an HSM ensures the organization has exclusive access.

Comprehensive and Detailed Explanation:

Adversary emulation simulates specific advanced persistent threat (APT) behaviors and techniques to test an organization’s security posture. In SecurityX CAS-005, this is part of red-teaming and purple-teaming strategies for realistic resilience testing.

Reliability factors (B) relate to operational uptime, not threat simulation.

Honeypots (C) attract attackers but do not directly emulate specific adversaries.

Internal reconnaissance (D) is one phase of an attack simulation, not the full emulation of advanced threat actors.

To ensure that logs from a legacy platform are properly retained beyond the default retention period, configuring the SIEM to aggregate the logs is the best approach. SIEM solutions are designed to collect, aggregate, and store logs from various sources, providing centralized log management and retention. This setup ensures that logs are retained according to policy and can be easily accessed for analysis and compliance purposes.

Determining if attacks are from the same actor requires unique attribution. Let’s analyze:

A. Code stylometry:Analyzes coding style to identify authorship, the best method for linking malware to a specific actor per CAS-005’s threat intelligence focus.

B. Common IOCs:Indicates similar attacks but not necessarily the same actor.

C. IOCextractions:Similar to B, lacks specificity for attribution.

The best solution to harden a three-tier environment (web, database, and application servers) is to implement microsegmentation on the server VLANs. Here’s why:

Enhanced Security: Microsegmentation creates granular security zones within the data center, allowing for more precise control over east-west traffic between servers. This helps prevent lateral movement by attackers who may gain access to one part of the network.

Isolation of Tiers: By segmenting the web, database, and application servers, the organization can apply specific security policies and controls to each segment, reducing the risk of cross-tier attacks.

Compliance and Best Practices: Microsegmentation aligns with best practices for network security and helps meet compliance requirements by ensuring that sensitive data and systems are properly isolated and protected.

To design resilience in an enterprise system that can survive environmental catastrophes, recover within 24 hours, and be resilient to active exploitation, the best strategy is to allocate fully redundant and geographically distributed standby sites. Here’s why:

Geographical Redundancy: Having geographically distributed standby sites ensures that if one site is affected by an environmental catastrophe, the other sites can take over, providing continuity of operations.

Full Redundancy: Fully redundant sites mean that all critical systems and data are replicated, enabling quick recovery in the event of a critical loss of availability.

Resilience to Exploitation: Distributing resources across multiple sites reduces the risk of a single point of failure and increases resilience against targeted attacks.

Based on the provided logs, the user has accessed various applications from different geographic locations within a very short timeframe. This pattern is indicative of the "impossible travel" security rule, a common feature in Single Sign-On (SSO) systems designed to detect and prevent fraudulent access attempts.

Analysis of Logs:

At 8:47 p.m., the user accessed a VPN from Toronto.

At 8:48 p.m., the user accessed email from Los Angeles.

At 8:48 p.m., the user accessed the human resources system from Los Angeles.

At 8:49 p.m., the user accessed email again from Los Angeles.

At 8:52 p.m., the user attempted to access the human resources system from Toronto, which was denied.

These rapid changes in location are physically impossible and typically trigger security measures to prevent unauthorized access. The SSO system detected these inconsistencies and likely flagged the activity as suspicious, resulting in access denial.

The best action to address the requirement of accessing the historian server within a SCADA system is to isolate the historian server for connections only from the SCADAenvironment. Here’s why:

Security and Isolation: Isolating the historian server ensures that only authorized devices within the SCADA environment can connect to it. This minimizes the attack surface and protects sensitive data from unauthorized access.

Access Control: By restricting access to the historian server to only SCADA devices, the organization can better control and monitor interactions, ensuring that only legitimate queries and data retrievals occur.

Best Practices for Critical Infrastructure: Following the principle of least privilege, isolating critical components like the historian server is a standard practice in securing SCADA systems, reducing the risk of cyberattacks.

To reduce the number of failed patch deployments, the systems administrator should implement a robust change management process. Change management ensures that all modifications to systems or applications are planned, tested, and approved before deployment. This systematic approach reduces the risk of unplanned changes that can cause patch failures and ensures that patches are deployed in a controlled and predictable manner.

RACI matrix(Responsible, Accountable, Consulted, Informed) is used for role mapping across the project lifecycle.

CMDB is a configuration inventory; ITIL is a framework. Recall trees are for disaster recovery/business continuity.

FromCAS-005, Domain 1: Security Governance and Compliance:

“The RACI matrix is essential in role assignment and accountability for software development and operational processes.”

Code-signing within theCI/CD pipelineensures that only verified and signed code is deployed, mitigating the risk of supply chain attacks. Updating Python withaptitudeand updating modules withpipensures vulnerabilities are patched. Deploying the solution to production after testing maintains application availability while securing the development lifecycle.

Branch protection (B)applies only to version-controlled environments, which is not the case here.

NFS network share (C)does not address the deprecated Python vulnerability.

Version designation (D)does not eliminate security risks from outdated dependencies.

The immediate action after discovering ransomware is toisolate the affected serversto prevent further spread of the malware to other systems in the network. Paying the ransom is not recommended as it does not guarantee data recovery and encourages criminal behavior. Notifying law enforcement is necessary, but containment must happen first to limit damage. Requesting server restoration should only occur after containment and a thorough investigation to ensure no remnants of ransomware remain.

WAP A: No issue found. The WAP A is configured correctly and meets therequirements.

PC A = Enable host-based firewall to block all traffic

This option will turn off the host-based firewall and allow all traffic to pass through. This will comply with the requirement and also improve the connectivity of PC A to other devices on the network. However, this option will also reduce the security of PC A and make it more vulnerable to attacks. Therefore, it is recommended to use other security measures, such as antivirus, encryption, and password complexity, to protect PC A from potential threats.

Laptop A: Patch management

This option will install the updates that are available for Laptop A and ensure that it has the most recent security patches and bug fixes. This will comply with the requirement and also improve the performance and stability of Laptop A. However, this option may also require a reboot of Laptop A and some downtime during the update process. Therefore, it is recommended to backup any important data and close any open applications before applying the updates.

Switch A: No issue found. The Switch A is configured correctly and meets the requirements.

Switch B: No issue found. The Switch B is configured correctly and meets the requirements.

Laptop B: Disable unneeded services

This option will stop and disable the telnet service that is using port 23 on Laptop B. Telnet is a cleartext service that transmits data in plain text over the network, which exposes it to eavesdropping, interception, and modification by attackers. By disabling the telnet service, you will comply with the requirement and also improve the security of Laptop B. However, this option may also affect the functionality of Laptop B if it needs to use telnet for remote administration or other purposes. Therefore,it is recommended to use a secure alternative to telnet, such as SSH or HTTPS, that encrypts the data in transit.

PC B: Enable disk encryption

This option will encrypt the HDD of PC B using a tool such as BitLocker or VeraCrypt. Disk encryption is a technique that protects data at rest by converting it into an unreadable format that can only be decrypted with a valid key or password. By enabling disk encryption, you will comply with the requirement and also improve the confidentiality and integrity of PC B’s data. However, this option may also affect the performance and usability of PC B, as it requires additional processing time and user authentication to access the encrypted data. Therefore, it is recommended to backup any important data and choose a strong key or password before encrypting the disk.

PC C: Disable unneeded services

This option will stop and disable the SSH daemon that is using port 22 on PC C. SSH is a secure service that allows remote access and command execution over an encrypted channel. However, port 22 is thedefault and well-known port for SSH, which makes it a common target for brute-force attacks and port scanning. By disabling the SSH daemon on port 22, you will comply with the requirement and also improve the security of PC C. However, this option may also affect the functionality of PC C if it needs to use SSH for remote administration or other purposes. Therefore, it is recommended to enable the SSH daemon on a different port, such as 4022, by editing the configuration file using the following command:

sudo nano /etc/ssh/sshd_config

Server A. Need to select the following:

A black and white screen with white text Description automatically generated

The most appropriate technique to improve the cryptographic strength of a password-storage component in a web application without completely replacing the crypto-module is key stretching. Here's why:

Enhanced Security: Key stretching algorithms, such as PBKDF2, bcrypt, and scrypt, increase the computational effort required to derive the encryption key from the password, making brute-force attacks more difficult and time-consuming.

Compatibility: Key stretching can be implemented alongside existing cryptographic modules, enhancing their security without the need for a complete overhaul.

Industry Best Practices: Key stretching is a widely recommended practice for securely storing passwords, as it significantly improves resistance to password-cracking attacks.