iSMTP Usage Example

Test a list of IPs from a file (-f smtp-ips.txt) enumerating usernames from a dictionary file (-e /usr/share/wordlists/metasploit/unix_users.txt):

root@kali:~# ismtp -f smtp-ips.txt -e /usr/share/wordlists/metasploit/unix_users.txt

 ---------------------------------------------------------------------
  iSMTP v1.6 - SMTP Server Tester, Alton Johnson (alton.jx@gmail.com)
 ---------------------------------------------------------------------

 Testing SMTP server [user enumeration]: 192.168.1.25:25
 Emails provided for testing: 109

 Performing SMTP VRFY test...

 [-] 4Dgifts ------------- [ invalid ]
 [-] EZsetup ------------- [ invalid ]
 [+] ROOT ---------------- [ success ]
 [+] adm ----------------- [ success ]

Packages and Binaries:

ismtp

Test for SMTP user enumeration (RCPT TO and VRFY), internal spoofing, and relay.

Installed size: 40 KB
How to install: sudo apt install ismtp

  • python3
ismtp
root@kali:~# ismtp -h

 Error: option -h requires argument

 ---------------------------------------------------------------------
  iSMTP v1.6 - SMTP Server Tester, Alton Johnson (alton.jx@gmail.com)
 ---------------------------------------------------------------------
 
 Usage: ./iSMTP.py <OPTIONS>

 Required:

	-f <import file>	Imports a list of SMTP servers for testing.
				(Cannot use with '-h'.)
	-h <host>		The target IP and port (IP:port).
				(Cannot use with '-f'.)

 Spoofing:

	-i <consultant email>	The consultant's email address.
	-s <sndr email>		The sender's email address.
	-r <rcpt email>		The recipient's email address.
	   --sr <email>		Specifies both the sender's and recipient's email address.
	-S <sndr name>		The sender's first and last name.
	-R <rcpt name>		The recipient's first and last name.
	   --SR <name>		Specifies both the sender's and recipient's first and last name.
	-m			Enables SMTP spoof testing.
	-a			Includes .txt attachment with spoofed email.

 SMTP enumeration:

	-e <file>	Enable SMTP user enumeration testing and imports email list.
	-l <1|2|3>	Specifies enumeration type (1 = VRFY, 2 = RCPT TO, 3 = all).
			(Default is 3.)

 SMTP relay:

	-i <consultant email>	The consultant's email address.
	-x			Enables SMTP external relay testing.

 Misc:

	-t <secs>	The timeout value. (Default is 10.)
	-o		Creates "ismtp-results" directory and writes output to
			ismtp-results/smtp_<service>_<ip>(port).txt

 Note: Any combination of options is supported (e.g., enumeration, relay, both, all, etc.).


Updated on: 2021-Nov-26