DNSWL.org Announces Changes

Whitelist provider DNSWL.org announced changes to its operating model. Who is DNSWL.org? "Dnswl.org is the leading whitelist provider for email filtering. It is being used by over 50'000 organisations worldwide, and contains close to 100'000 entries of 'good mailservers.' Your email filter should try to avoid tagging messages as spam, if they come from one of those good mailservers."

As announced on their website and on multiple mailing lists today: "As announced earlier, dnswl.org will change it's operating model. "Heavy users" (defined as those doing > 100'000 queries/24 hours on the public nameservers) and vendors of anti-spam products and services will need a paid subscription.

We are now ready to implement the model and will gradually start to enforce it. Since we do not know the current users (all we have are IPs and sometimes hostnames), we will also need to "cut off" users if our attempts at identifying and notifying them fail.

The "cut off" may have two of effects: 1) rsync suddenly stops working 2) queries on the public nameservers are refused. We may be able to reinstate access on a case by case basis.

As usual, we can be reached at admins/at/dnswl.org (or office/at/dnswl.org for direct access to the people handling the subscriptions). All details are available from http://www.dnswl.org/ "

Spews.org Domain Expired

Thanks for Joe Sniderman for the tip that the domain spews.org has expired and was grabbed up by somebody that appears to be a domain speculator or parked domain monetizer. The SPEWS blocking list is long-dead, since August, 2006.

Status of ybl.megacity.org: DEAD

There once was a DNSBL called ybl.megacity.org. Exactly when it was created is lost to the mists of time, but I'm guessing it was somewhere around the end of 2001 or beginning of 2002, after its maintainer, Derek Balling, parted ways with Yahoo. I recall that the point of the list was to be able to reject mail from Yahoo.

Today, reader John Carver kindly wrote in to let me know that this blocking list is indeed defunct and has "listed the world," installing a wildcard DNS record with the result that if you use ybl.megacity.org in your mail server configuration, you're going to reject 100% of your mail. Query of any domain or IP address under ybl.megacity.org will result in a "" positive response, that will make a mail server think it should reject the email message in question.

If you use ybl.megacity.org as a DNSBL list in your mail server configuration, I strongly recommend you remove it immediately. The list is long dead, and use of the list will result in you accidentally rejecting 100% of inbound mail.

As recently as 2006, the DNSBL also responded with text warning that it was defunct: "521 The IP is Blacklisted by ybl.megacity.org. This zone has been deprecated for about two years. Maybe if it starts blocking your mail you'll notice and stop using it." This is no longer the case; the text record does not seem to be present.

See also the Ipswitch ImailServer knowledge base article on this topic.

Beware: "Fake" Blocking list at nszones.com

Spamhaus reports that they have "uncovered a fake spam filter company which was pirating and selling DNSBL data stolen from major anti-spam systems including Spamhaus, CBL and SURBL, republishing the stolen data under the name 'nszones.com.'"

Ouch. I guess if you publish a free or easily accessed spam filtering tool, it is inevitable that at some point somebody would try to take the data and repackage it against copyright and against the data owner's wishes.

If you find yourself listed on this blocking list; don't fret. If what Spamhaus says is true (and I have little reason to doubt them), then this list is not really being used to block email. (And should not be used to block email.) Ignore it, stay listed, and eventually they'll move on to easier targets.

If you're a system administrator, DO NOT use any of the DNSBL zones at nszones.com for spam filtering purposes. As its intent may not be above-board, I would have strong concerns about the possibility of listing things only to engender a payment for delisting -- for reasons having nothing to do with spam fighting.