Nessus is best described as which of the following?

• A. Firewall
• B. Vulnerability scanning tool
• C. Password cracker
• D. Network management tool.

Answer: (B)

Nessus is a vulnerability scanning tool used to identify weaknesses across systems and applications. It works by scanning hosts for known vulnerabilities, misconfigurations, missing patches, and weak credentials through a large library of plugins tied to CVEs and configuration checks. The results let you prioritize remediation by showing which systems are most at risk and what patches or changes are needed. It isn’t a firewall (it doesn’t filter traffic), a password cracker (it doesn’t break passwords), or a network management tool (it doesn’t manage devices). After scanning, you review the findings, verify them, and plan fixes accordingly.