bmw
September 16th, 2003, 09:45
As of last night, Verisign has changed their DNS servers to return an IP rather than "not found" when you lookup an address that doesn't exist. If you do an nslookup on "verisignarecompletebastards.com" you get 64.94.110.11. This address returns a "search page" (thinly diguised advertising) to a web browser.
See http://slashdot.org/articles/03/09/16/0034210.shtml?tid=126&tid=95&tid=98&tid=99
But worse, it hurts anti-spam measures. Modern MTAs will check that the sender's domain exists before accepting it. If it isn't real, you can't reply to it, so it's 99.99% certain to be spam. Now, all addresses in .com and .net appear to be real.
The best defense against this appears to be to hack the DNS resolvers and/or their libraries to return a not-found result if the returned address happens to match the IP(s) for "sitefinder*.verisign.com".
Russell Nelson has hacked djbdns already ...
From: Russell Nelson <nelson@crynwr.com>
Date: Mon, 15 Sep 2003 23:38:19 -0400
To: qmail list <qmail@list.cr.yp.to>, dns@list.cr.yp.to
Subject: Re: Verisign adds wildcards
Russell Nelson writes:
> Working on a patch to djbdns that rejects A records that resolve to
> 64.94.110.11. Returns NXDOMAIN.
Got it.
http://tinydns.org/djbdns-1.05-ignoreip.patch
Work is underway on BIND 8.
See http://slashdot.org/articles/03/09/16/0034210.shtml?tid=126&tid=95&tid=98&tid=99
But worse, it hurts anti-spam measures. Modern MTAs will check that the sender's domain exists before accepting it. If it isn't real, you can't reply to it, so it's 99.99% certain to be spam. Now, all addresses in .com and .net appear to be real.
The best defense against this appears to be to hack the DNS resolvers and/or their libraries to return a not-found result if the returned address happens to match the IP(s) for "sitefinder*.verisign.com".
Russell Nelson has hacked djbdns already ...
From: Russell Nelson <nelson@crynwr.com>
Date: Mon, 15 Sep 2003 23:38:19 -0400
To: qmail list <qmail@list.cr.yp.to>, dns@list.cr.yp.to
Subject: Re: Verisign adds wildcards
Russell Nelson writes:
> Working on a patch to djbdns that rejects A records that resolve to
> 64.94.110.11. Returns NXDOMAIN.
Got it.
http://tinydns.org/djbdns-1.05-ignoreip.patch
Work is underway on BIND 8.