Autor: Chris Edwards
Data:
Dla: exim-users
Temat: [Exim] HELO syntax check
This week's favourite spamware seems to greet us with (literally):
HELO $domain
which is illegal and should be rejected. Sure enough, our 4.10 boxes
respond with:
501 Syntactically invalid HELO argument(s)
which should make a real client go away. But, sadly the spammer ignores
the 501 and sends the spam anyway, which we accept and deliver :-(
Can exim be set up to reject in this case ?
Note we only wish to enforce syntax, not check HELO matches reverse DNS
with helo_verify_hosts and friends.
Not a big problem :)
Chris
exim -bP | grep helo
helo_accept_junk_hosts =
helo_allow_chars = _
helo_lookup_domains = @ : @[]
helo_try_verify_hosts =
helo_verify_hosts =
220 hillhead.cent.gla.ac.uk ESMTP Exim 4.10 Wed, 21 Aug 2002 12:05:27 +0100
HELO $domain
501 Syntactically invalid HELO argument(s)
MAIL FROM: <>
250 OK
RCPT TO: <postmaster@???>
250 Accepted