iSMTP چیست؟

ابزار iSMTP یکی از ابزار هایی است که در زمینه شناسایی کاربران مجاز سرویس SMTP فعالیت می کند. در اصل این ابزار وظیفه SMTP User Enumeration را بر عهده دارد.

لینک منبع: https://github.com/altjx/ipwn
لایسنس: GPLv2
سازنده: Alton Johnson

نمونه دستور:

root@regux.com:~# ismtp

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

 Usage: ./iSMTP.py

 Required:

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

 Spoofing:

    -i       The ISA's email address.
    -s      The sender's email address.
    -r      The recipient's email address.
       --sr      Specifies both the sender's and recipient's email address.
    -S       The sender's first and last name.
    -R       The recipient's first and last name.
       --SR       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    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       The ISA's email address.
    -x          Enables SMTP external relay testing.

 Misc:

    -t    The timeout value. (Default is 10.)
    -o      Creates "ismtp-results" directory and writes output to
            ismtp-results/smtp__(port).txt

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

نمونه عملکرد واقعی دستور:

در دستور زیر، یک لیست از IP برگرفته شده از فایل (f smtp-ips.txt-) تحت حمله Dictionary با استفاده از لیست (-e /usr/share/wordlists/metasploit/unix_users.txt) قرار می گیرد.

root@regux.com:~# 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 ]