CompTIA CAS-004 Exam

ssdeep is a tool that computes and matches Context Triggered Piecewise Hashing (CTPH), also known as fuzzy hashing. It can be used to identify similar files or slight variations of the same file, which may point to the creator of the file if certain patterns or markers are consistently present. This method allows for integrity checking without altering the evidence, which is critical in forensic investigation.

The SIEM logs indicate suspicious behavior that could be a sign of a compromise, such as the launching of cmd.exe after Outlook.exe, which is atypical user behavior and could indicate that a machine has been compromised to perform lateral movement within the network. Isolating laptop314 from the network would contain the threat and prevent any potential spread to other systems while further investigation takes place.

Using digital certificates for authentication is a secure method to control access to laptops and other devices. A device certificate can serve as an authenticator by providing a means for the device to prove its identity in a cryptographic manner. This certificate-based authentication is commonly used in enterprise environments for strong authentication.

Calculating the Annual Loss Expectancy (ALE) and conducting a cost-benefit analysis is a critical part of risk management. The ALE will help the company understand the potential losses associated with the server failure per year, which can then be weighed against the cost of mitigating the risk (e.g., replacing the server or implementing redundancies). This analysis will inform the decision on the best course of action to manage the risk associated with the aging server.

Input validation is a technique that checks the user input for any errors, malicious data, or unexpected values before processing it by the application. Input validation can prevent many common web application attacks, such as:

SQL injection, which exploits a vulnerability in the application's database query to execute malicious SQL commands.

Cross-site scripting (XSS), which injects malicious JavaScript code into the application's web page to execute on the client-side browser.

Directory traversal, which accesses files or directories outside of the intended scope by manipulating the file path.

In this case, the security engineer should recommend input validation as the best mitigation technique, because it would:

Prevent the exfiltration of a company report by validating the file parameter in the URL and ensuring that it matches a predefined list of allowed files or formats.

Enhance the security of the web application by filtering out any malicious or invalid input from users or attackers.

Be more effective and efficient than other techniques, such as firewall, WAF (Web Application Firewall), or DLP (Data Loss Prevention), which may not be able to detect or block all types of web application attacks.