[Mimedefang] Validate forged local sender

[Stephen Carr]

Dear list

I am trying to block spams that have the sender forged as a non existent
user in our domain but the recipient is a valid email address.

Sendmail is configured with LUSER_RELAY that has a list valid users -
returns "nouser User unknown" if user does not exist.

I have searched the web with no success.

Any pointers will be appreciated.

Thanks
Stephen Carr

Current config
Sendmail-8.14.3
MimeDefang-2.65
Spamassassin-3.2.5
DSPAM-3.6.8

--
Stephen Carr
Computing Officer
School of Civil and Environmental Engineering
The University of Adelaide
Tel +618-8303-4313
Fax +618-8303-4359
Email sgcarr at civeng.adelaide.edu.au

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