CompTIA CS0-003 Exam With Confidence Using Practice Dumps

The suspicious entry on the host-based IDS logs indicates that a reverse shell was executed on the host, which connects to the remote IP address 10.1.2.3 on port 8080. The shell script option D uses the netstat command to check if there is any active connection to that IP address and port, and prints “Malicious activity” if there is, or “OK” otherwise. This is the most accurate way to confirm if the reverse shell is still active, as the other options may not detect the connection or may produce false positives.

ReferencesCompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 8: Incident Response, page 339.Reverse Shell Cheat Sheet, Bash section.

The correct answer is A because path traversal, also called directory traversal, occurs when an attacker manipulates file or directory path input, such as ../, to access files outside the intended directory. The best code-level fix is to validate and sanitize user-supplied file and directory names so the application does not accept traversal sequences or malicious path characters.

Exact supporting extract: the Sybex CySA+ Study Guide explains that a directory traversal attack occurs when an attacker inserts filesystem path values into a query string to access files outside the authorized area. It also states that controls should include avoiding filenames in user-manipulatable fields and using input validation to prevent special characters required for directory traversal.

The All-in-One CySA+ guide also states that directory traversal mitigations include input validation to ensure user input does not contain directory traversal sequences and filename sanitization to remove directory traversal sequences or other malicious characters.

Why the other options are incorrect:

B is incorrect because output encoding is mainly used to prevent output-based attacks such as XSS.

C is incorrect because scrubbing SQL commands relates to SQL injection, not path traversal.

D is a useful defense-in-depth measure, but it does not directly rewrite the vulnerable code to prevent path traversal.