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Vulnerability Assessment Details

EXPN and VRFY commands

Vulnerability Assessment Summary
EXPN and VRFY checks

Detailed Explanation for this Vulnerability Assessment

The remote SMTP server answers to the EXPN and/or VRFY commands.

The EXPN command can be used to find the delivery address of mail aliases, or
even the full name of the recipients, and the VRFY command may be used to check the validity of an account.

Your mailer should not permit remote users to use any of these commands,
because it gives them too much information.

Solution : if you are using Sendmail, add the option :

O PrivacyOptions=goaway

in /etc/sendmail.cf.

Network Security Threat Level: Low

Networks Security ID:

Vulnerability Assessment Copyright: This script is Copyright (C) 1999 Renaud Deraison

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