On Wed, 2005-12-28 at 13:17 +0000, Alan J. Flavell wrote:
> I've just been re-reading http://www.spambag.org/backscatter.html
>
> It appears that this chap takes the view that there can be no
> exceptions; but he offers no viable way of dealing with forwarded
> addresses nor with vacation responses. While I have a great deal of
> sympathy with the rest of what he says, I'm at a loss to know how to
> deal with this aspect.
>
> If he contrives to produce a probe which, as a result of forwarding or
> vacation response at the probed MTA, results in a bounce being
> delivered to his spamtrap, then he'll blacklist the site in question.
> There's definitely a (small) risk that we could do that, if we ever
> came to his attention (which we, fortunately, haven't).
we are using a sacrificial IP address. outbound messages with SA score
3+ (forwarded spam) or sender <> (bounces and vacation messages) are
sent from a different IP address than the main bulk of our traffic. we
use a separate Exim configuration and queue to handle this. even if
Spamcop or others lists this address from time to time, the potential
for harm is quite small.
(we used to use Spamcop to block e-mail outright, but occasionally
they're too aggressive, so we add 3 SpamAssassin points instead now.)
--
Kjetil T.
