Re: closing exims open relay - something to do with the percent hack
On Wed, 2003-07-02 at 01:09, Shri Shrikumar wrote:
> Hi,
>
> I just did an open relay test on one of my servers and to my surprise
> found that it in an open relay. In particular, it accepts emails to the
> form of
>
> someone%somewhereelse.com@here.com
>
> where here.com is a local domain within exim.
Check the bug reports on exim. There is a case where a stock standard
Debian install of exim (and possibly postfix) can turn out to be an open
relay.
What happens is the the "satellite" email server blindly forwards email
to the smart-host, and the smart-host blindly trusts the satellite
system because it's within the trusted domain. Between the two of them
they become an open relay.
--
Donovan Baarda <abo@minkirri.apana.org.au>
http://minkirri.apana.org.au/~abo/
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