What does the -sV option do in Nmap?

What does the -sV option do in Nmap?

• A. It performs an initial ping sweep.
• B. It enables service/version detection to identify running software.
• C. It enables script scanning.
• D. It increases the retry count.

Answer: (B)

The main idea this question tests is how Nmap identifies exactly what software is running on open ports, not just which ports are reachable. The -sV option enables service and version detection, so Nmap probes the services it discovers and compares the responses to a database to tell you the service name and often the specific version (for example, an HTTP server like Apache/2.4.41). This is the best answer because it matches the purpose of -sV: to reveal what software is running on each open port and which version of that software is present. Knowing the service and version is crucial for vulnerability assessment and inventory. Other options describe different functionality. A ping sweep is about discovering which hosts are up, not identifying running services. Script scanning uses the Nmap Scripting Engine to run NSE scripts for additional checks. Increasing the retry count changes how many times Nmap resends probes, affecting scan thoroughness and timing rather than identifying services or versions.

The main idea this question tests is how Nmap identifies exactly what software is running on open ports, not just which ports are reachable. The -sV option enables service and version detection, so Nmap probes the services it discovers and compares the responses to a database to tell you the service name and often the specific version (for example, an HTTP server like Apache/2.4.41).

This is the best answer because it matches the purpose of -sV: to reveal what software is running on each open port and which version of that software is present. Knowing the service and version is crucial for vulnerability assessment and inventory.

Other options describe different functionality. A ping sweep is about discovering which hosts are up, not identifying running services. Script scanning uses the Nmap Scripting Engine to run NSE scripts for additional checks. Increasing the retry count changes how many times Nmap resends probes, affecting scan thoroughness and timing rather than identifying services or versions.