o Click Start then select Control Panel.
o Select Programs and Features.
o Select Turn Windows features on or off.
o Select the Telnet Client option and click OK.
o A box will appear to confirm installation. The telnet command should now be installed
1. First, the hacker would choose one of the open ports that were revealed in the Nmap scan to continue with and attempt to exploit. Let’s say that when the hacker scanned his target, he found the port 21 open. As you can see on the chart above, port 21 is FTP. To find out what FTP software is running he would use telnet by running the command:
telnet www. targetsite.com 21
As you can see above, I ran this against my computer (localhost). So a hacker would insert a target URL in place of localhost.
2. Next, it would connect to the target and display a banner telling the hacker the software and its version as shown below. This is the information the hacker needs to continue and begin searching for vulnerabilities for the software discovered.
If the above method doesn’t work for you, then simply use Nmap’s full version.
Above article posted by Mr. Vishal Shah (Cyber Crime Investigator - Gujrat)