Hands-On Penetration Testing with Kali NetHunter

Exercise – working with smtp-user-enum

The second tool we can use is smtp-user-enum, which is a Perl script designed to determine user names via SMTP, among other tasks. To run smtp-user-enum, open the Terminal and issue the smtp-user-enum command with the desired switches. Let's take a look at some examples of the script commands.

The following examples use the same server address from before with nmap (here I noted the address with an <IP> tag instead of the full address for clarity):

smtp-user-enum -M VRFY -U names.txt -t <IP>  
smtp-user-enum -M EXPN -U names.txt -t <IP>  
smtp-user-enum -M RCPT -U names.txt -t <IP>  

You should notice with these commands that we have a series of switches; let's take a look at these three commands that are ...