[cobalt-users] Speaking of Stopping Spam

["Dan Kriwitsky" <list1@xxxxxxxxxxxxxxxxxxxx>]

OK DNS gurus. Put on your thinking caps.

Until today, when someone tries to send you email from some fake domain,
such as dan@xxxxxxxxxxxxxx the server would reject it:

501 5.1.8 <dan@xxxxxxxxxxxxxx>... Domain of sender address
dan@xxxxxxxxxxxxxx does not exist

Now, Verisign is taking over the entire .net and .com so that when you
type a domain that doesn't exist, it resolves to 64.94.110.11 or some IP
64.94.110.0/24. Now you get:

> MAIL FROM: <dan@xxxxxxxxxxxxxx>
250 2.1.0 <dan@xxxxxxxxxxxxxx>... Sender ok

And, unless the IP is blacklisted in access or a DNSBL that you're
checking, it's going to get through so the approx. line 1114 of
sendmail.cf is useless.

R<TEMP> $*		$#error $@ 4.1.8 $: "451 Domain of sender
address " $&f " does not resolve"
R<PERM> $*		$#error $@ 5.1.8 $: "501 Domain of sender
address " $&f " does not exist"

More:

http://slashdot.org/article.pl?sid=03/09/11/2326205

Someone familiar with Exim said you can place ignore_target_hosts =
64.94.110.11 in your lookuphosts router. Anyone know of something
similar for the RaQ for Sendmail?

-- 
Dan Kriwitsky
4Sarasota.com [TM]
941-918-1967