smtp-user-enum

Enumerate valid users via SMTP.

KaliParrotlow

pkg: smtp-user-enum

smtp-user-enum guesses valid system users through SMTP VRFY/EXPN/RCPT verbs.

Syntax

smtp-user-enum -M {mode} -U {users} -t {host}

Example

smtp-user-enum -M VRFY -U users.txt -t 10.0.0.5

Uses VRFY to test which usernames the mail server accepts.

Advantages
  • Builds valid user lists
  • Simple
Disadvantages
  • Often disabled on modern MTAs
  • Noisy
Tags
#smtp#enumeration

Official docs: smtp-user-enum

Related commands

Frequently asked questions

What is smtp-user-enum used for?
smtp-user-enum guesses valid system users through SMTP VRFY/EXPN/RCPT verbs.
What is an example smtp-user-enum command?
A common example is: smtp-user-enum -M VRFY -U users.txt -t 10.0.0.5 — Uses VRFY to test which usernames the mail server accepts.
Is smtp-user-enum part of Kali Linux?
Yes. smtp-user-enum ships with Kali Linux (and Parrot OS). If missing, install it with: sudo apt install smtp-user-enum.
What category of security tool is smtp-user-enum?
smtp-user-enum is a Information Gathering tool with a low-risk profile when run against a live target.

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