Am 18.04.10 14:37, schrieb Charles Marcus:
On 2010-04-18 8:10 AM, Marcus Frischherz wrote:
The spam gets filtered alright by spamassassin, and then it bounces, but
it doesn't bounce to the actual real originator, but to the local user.
So in this way the spammer manages to deliver the spam to the addrassee,
although it is filtered my spamassassin, abusing the bounce concept.
That is your problem. Either set up your anti-spam filter as a pre-queue
filter, so you can smtp reject it, rather than accept>bounce it, or do
*not* bounce it but deliver it tagged and/or to a spam folder.
What you are enagging in is called backscatter, and can eventually get
you blacklisted if your server is high enough volume:
http://www.postfix.org/BACKSCATTER_README.html
Thanks for the link. I read it, and I realize that it is related to my
problem. However, this link describes how to block incoming bckscatter,
while my problem seems to be, that postfix with these settings creates
backscatter (maybe relaying it to outside users as well, certainly, as
evidenced by my mail box, internally). This is exactly the reason why I
want to disable the bounce, and the question is how. Temporarilly I
commented out the line
#bounce unix - - n - 0 bounce
in master.cf, but I think that this is not the ideal solution, as now
undeliverable mails start queuing up.
regards,
Marcus
