CAS-005 Exam Dumps - CompTIA SecurityX Certification Exam

To secure the Operational Technology (OT) environment based on the given requirements, the best approach is to implement a bastion host inthe OT network. The bastion host serves as a secure entry point for remote access, allowing third-party vendors to connect while being monitored by security tools. Using a dedicated update server for workstations ensures that security updates are applied in a controlled manner without direct internet access.

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.

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 way to mitigate the ability of attackers or penetration testers to execute arbitrary payloads is to enforce application controls with allow lists (B). Application allow listing ensures that only pre-approved, trusted software and scripts can be executed on the system. This prevents attackers from dropping or running malicious binaries, even if they exploit vulnerabilities to gain access. CAS-005 emphasizes allow listing as a preventive control against post-exploitation persistence and lateral movement.

Option A (ASLR) randomizes memory addresses and helps mitigate buffer overflow exploits but does not directly prevent execution of unauthorized programs. Option C (OS restrictions of globally writable folders) improves security hygiene but still does not stop attackers from executing already placed payloads in non-restricted locations. Option D (EDR signatures) are reactive and limited, since attackers often use novel or obfuscated payloads not yet captured by signature databases.

Therefore, implementing application controls with allow lists provides the strongest defense against unauthorized payload execution in this context.

Sinkholing, or DNS sinkholing, is a method used to redirect malicious traffic to a safe destination. This technique is often employed by security teams to prevent access to malicious domains by substituting a benign destination IP address.

In the given logs, users from the finance department are accessing www.bank.com and receiving HTTP status code 495. This status code is typically indicative of a client certificate error, which can occur if the DNS traffic is being manipulated or redirected incorrectly. The consistency in receiving the same HTTP status code across different users suggests a systematic issue rather than an isolated incident.

Recursive DNS resolution failure (A) would generally lead to inability to resolve DNS at all, not to a specific HTTP error.

DNS poisoning (B) could result in usersbeing directed to malicious sites, but again, would likely result in a different set of errors or unusual activity.

Incorrect DNS setup (D) would likely cause broader resolution issues rather than targeted errors like the one seen here.

By reviewing the provided data, it is evident that the DNS traffic for www.bank.com is being rerouted improperly, resulting in consistent HTTP 495 errors for the finance department users. Hence, the most likely cause is that the DNS traffic is being sinkholed.

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.

The most appropriate solution for the systems engineer to deploy is SELinux (Security-Enhanced Linux). Here ' s why:

Mandatory Access Control (MAC): SELinux enforces MAC policies, ensuring that only authorized users and processes can access specific resources. This helps in preventing unauthorized reading and modification of data and programs.

Access Vector Cache: SELinux utilizes an access vector cache (AVC) to improve performance. The AVC caches access decisions, reducing the need for repetitive policy lookups and thus improving system efficiency.

Security Mechanisms: SELinux provides a robust framework to enforce security policies and prevent bypassing of application security mechanisms. It controls access based on defined policies, ensuring that security measures are consistently applied.

Privilege Escalation and Process Interference: SELinux limits the ability of processes to escalate privileges and interfere with each other by enforcing strict access controls. This containment helps in isolating processes and minimizing the risk of privilege escalation attacks.

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.