[Kolab-devel] [issue2833] Mail filter setting "Always reject" should reject instead of bounce

[Thomas Arendsen Hein]

New submission from Thomas Arendsen Hein <thomas at intevation.de>:

Mail Filter Settings -> Always reject the message...

This does not reject the message on the SMTP level, but happily accepts this:

$ telnet mail.example.com 25
Trying 192.168.0.1...
Connected to example.com.
Escape character is '^]'.
220 example.com ESMTP Postfix
HELO foo
250 mail.example.com
MAIL FROM: user at example.com
250 2.1.0 Ok
RCPT TO: user at example.com
250 2.1.5 Ok
DATA
354 End data with <CR><LF>.<CR><LF>
From: user at example.com
To: user at example.com
Subject: foo

foo
.
250 2.0.0 Ok: queued as 500C41086A0A
QUIT
221 2.0.0 Bye


After this it sends a bounce message to user at example.com:

<user at example.com>: permission denied. Command output: Invalid From: header.
    user at example.com looks like a forged sender


I think this should be rejected earlier, because we already assume that
the address is forged. And we already know that user at example.com hasn't
authenticated itself.

----------
messages: 15432
nosy: bernhard, martin, thomas, till, wilde, wrobel
priority: feature
status: unread
title: Mail filter setting "Always reject" should reject instead of bounce
topic: server
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Kolab issue tracker <kolab-issues at intevation.de>
<https://www.intevation.de/roundup/kolab/issue2833>
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