Fingerprinting OSes and services running on a target

Version detection and OS detection are two of the most important features of Nmap. Nmap is known for having the most comprehensive OS and service fingerprint databases, contributed to over the years by millions of users. Knowing the OS and the exact software version of a service is highly valuable for people looking for security vulnerabilities or monitoring their networks for any unauthorized changes. Fingerprinting services may also reveal additional information about a target, such as available modules, last time of update, database version, and sometimes additional protocol information.

This recipe shows how to fingerprint the OS and running services of a remote host using Nmap.

How to do it...

1. To enable service detection, add the Nmap -sV option to your port scan command:

   $ nmap -sV <target>

2. The -sV option adds an additional column named VERSION that displays the specific software version. Additional information...