Free CompTIA CAS-005 Practice Exam with Questions & Answers | Set: 3

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.

Step-by-Step Explanation:

Regression testing ensures that new changes do not break existing functionality. It would have identified the memory leak before deployment, preventing downtime.

Homomorphic encryption allows computations to be performed on encrypted data without decrypting it, providing strong privacy guarantees. However, the adoption of homomorphic encryption is challenging due to several factors:

A. Incomplete mathematical primitives: This is not the primary barrier as the theoretical foundations of homomorphic encryption are well-developed.

B. No use cases to drive adoption: There are several compelling use cases for homomorphic encryption, especially in privacy-sensitive fields like healthcare and finance.

C. Quantum computers not yet capable: Quantum computing is not directly related to the challenges of adopting homomorphic encryption.

D. Insufficient coprocessor support: The computational overhead of homomorphic encryption is significant, requiring substantial processing power. Current general-purpose processors are not optimized for the intensive computations required by homomorphic encryption, limiting its practical deployment. Specialized hardware or coprocessors designed to handle these computations more efficiently are not yet widely available.

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.

Encrypting patient data at rest is a critical requirement for healthcare providers to ensure compliance with regulations such as the Health Insurance Portability and Accountability Act (HIPAA). The primary business requirement fulfilled by this practice is the protection of patient privacy while supporting the portability of medical information. By encrypting data at rest, healthcare providers safeguard sensitive patient information from unauthorized access, ensuring that privacy is maintained even if the storage media are compromised. Additionally, encryption supports the portability of patient records, allowing for secure transfer and access across different systems and locations while ensuring that privacy controls are in place.

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.

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 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.

Animmutable databasepreventsmodifications or deletions, ensuring resilience against ransomware while maintaining multiple copies of data.

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.