Am 27.08.2012 13:17, schrieb Jan Geep:
[...] until recently people have started
receiving spam email that appear to be sent from my domain.
For example
From: myn...@example.com
To: myn...@example.com
Subject: Fwd: Re: Scan from a Hewlett-Packard ScanJet 1234
But the return path is along the lines of:
Return-Path: <somen...@spammer.com>
[...]
Example header of Spam:
Return-Path: <somen...@spammer.com>
Delivered-To: myn...@example.com
Received: from mail.example.com (gateway.localhost [10.0.0.1])
by mail-int (Postfix) with ESMTP id 59CC1211180
for <myn...@example.com>; Tue, 01 Aug 2012 12:00:00 +0100 (IST)
Received: from localhost (localhost [127.0.0.1])
by mail.example.com (Postfix) with ESMTP id 43EE4C0F5
for <myn...@example.com>; Tue, 01 Aug 2012 12:00:00 +0100 (IST)
Received: from mail.example.com ([127.0.0.1])
by localhost (mail.example.com [127.0.0.1]) (amavisd-maia, port 20004)
with ESMTP id 21183-01-6 for <myn...@example.com>;
Tue, 01 Aug 2012 12:00:00 +0100 (IST)
Received: from [xx.xx.xx.xx] (unknown [xx.xx.xx.xx])
by mail.example.com (Postfix) with ESMTP id 946DBC0EB
for <myn...@example.com>; Tue, 01 Aug 2012 12:00:00 +0100 (IST)
[...]
smtpd_recipient_restrictions = permit_sasl_authenticated,
permit_mynetworks,..., check_sender_access
hash:/etc/postfix/not_our_domain_as_sender
with /etc/postfix/not_our_domain_as_sender
example.com REJECT Sorry, sender not permitted!
This is derived from an example on Ralf Hildebrandts site
(http://www.arschkrebs.de/postfix/postfix_restriction_classes3_en.shtml)
good luck!
