Free Practice Questions for CompTIA CAS-005 Exam

When differentiating between valid and invalid findings from vulnerability scans, the systemsadministrator should verify that the scanning credentials are properly configured. Valid credentials ensure that the scanner can authenticate and access the systems being evaluated, providing accurate and comprehensive results. Without proper credentials, scans may miss vulnerabilities or generate false positives, making it difficult to prioritize and address the findings effectively.

HMAC (Hash-based Message Authentication Code)ensures the integrity and authentication of API requests without exposing static or hard-coded private keys. It uses a secret key and a hash function, preventing replay attacks and tampering. VPNs secure the transport layer, MFA protects user accounts (not API-to-database communications), and DSA is a signature algorithm but does not address hard-coding risk directly.

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.

Attack surface reductionfocuses on minimizingunnecessary services, open ports, and vulnerabilities, reducing the exposure to potential adversaries. This aligns withzero trust and least privilege principles.

Secure Boot (A)helps ensure system integrity but does not minimize exposed services.

Disabling third-party integrations (C)may help, but broader attack surface reduction is the best first step.

Limiting access (D)is important but does not directly reduce exposed services.

The code snippet exposes a hardcoded access token in a public repository. According to SecurityX CAS-005 secure coding best practices, the immediate action must be to revoke the exposed secret to prevent unauthorized access.

Removing the code from public view without revoking the token leaves the secret still usable by any attacker who has already seen or copied it.

SAST scanning would detect the issue but not mitigate it immediately.

Security awareness training is a long-term prevention measure but does not fix the immediate exposure.Revoking the secret first stops ongoing exploitation, after which the code can be removed, and preventative measures can be implemented.

Per SecurityX CAS-005 GRC principles, outsourcing a function does not transfer accountability for protecting personally identifiable information (PII). While subprocessors handle data, the originating organization remains responsible under most data protection laws and frameworks (e.g., GDPR, CCPA).

Due care in procurement (option B) is important, but it is a supporting concept, not the primary driver in this context.

Jurisdictional compliance (option D) is a requirement, but the underlying reason for risk assessment is that accountability for PII protection remains with the organization.

Incident response follows a standard process (e.g., NIST 800-61): Preparation, Identification, Containment, Eradication, Recovery, Lessons Learned. After identifying the attack (file and origin), the next step isContainment—limiting the spread or impact (e.g., isolating systems) before remediation or recovery.

Option A:Remediation (fixing the root cause) follows containment.

Option B:Correct—containment prevents further damage post-identification.

Option C:“Response” is too vague; it encompasses all steps.

Option D:Recovery (restoring systems) comes after containment and eradication.

The best solution is to use Self-Encrypting Drives (SEDs). SEDs automatically encrypt all data stored on the disk and can be rapidly sanitized or obfuscated by deleting or altering the encryption keys. This provides immediate and secure protection if customs agents demand device access, as the sensitive data inside containers becomes unreadable without the decryption key.

Option B (eFuse) and C (UEFI) are hardware mechanisms unrelated to dynamic data protection. Option D (vTPM) provides virtualized key storage but does not obfuscate data quickly under inspection conditions. Option E (MicroSD HSM) is useful for key storage but does not protect all data at scale.

CAS-005 highlights hardware-based encryption solutions like SEDs for protecting sensitive data during travel, ensuring both regulatory compliance and rapid response capabilities under hostile conditions.

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.