Spamhaus comments on subscription attack

Steve Linford, CEO of Spamhaus commented on my blog post about the current listings. I’m promoting it here as there is valuable information in it.

Excellent well summarized article Laura ?
No we’ve not changed SBL policy to require COI. It’s something we very strongly advise but we can not make a requirement. We’ll have to consider it if list-bombing of this magnitude can not be kept in check by list managers.
This incident involved a large number of government addresses belonging to various countries being subscribed to very large numbers of lists in a very short space of time by scripts run by the attacker(s). Most of the lists hit by the attack used COI and therefore only sent confirmation requests and did not subscribe any addresses. The attack undoubtably also hit lists which used Captcha in addition to COI and thus did not even proceed to COI (those list admins deserve some sort of community ‘hi 5’ award, since one can imagine how hard it is to convince one’s management to implement COI let alone put Captcha in front of it).
The issue is the badly-run ‘open’ lists which happily subscribed every address without any consent verification and which now continue as participants in the list-bombing of government addresses. These we are trying to address with SBL listings to prompt resolution by the Senders. As you noticed, most of these particular incident listings are for IPs ending “.0/32” which does not cause any mail issue to the Sender and is deliberately used where we have a good relationship with the Sender and know they will act quickly on the alert.
Steve Linford
Chief Executive
The Spamhaus Project

Efforts are ongoing to help ESPs clean up. Multiple commenters have been sharing data in the comments. If you have data you’d like to share with others, but don’t want to share it publicly please contact me directly.

Related Posts

Spamhaus under major dDOS

Late last night I, and a number of other folks, received mail from Spamhaus informing us of a major denial of service attack against their servers. The attack is so bad that the website and main mailserver is currently offline.
DNS services, including rsync and the mirrors, are up and running.
Spamhaus is working to bring the mailserver and website back up, and are hoping to have it up later today.
If there are any critical or particularly urgent SBL issues today, contact your ESP delivery team. The folks who were contacted do have an email address for urgent issues. This is not an address for routine queries, however, and most listees are going to have to wait until normal services are restored to have their listing addressed.
If there is something particularly urgent and your ESP or delivery team does not have a contact address, you can contact me an I can see what I can do.
UPDATE: Most of the IPs people have sent me are actually XBL/CBL listings. But right now the CBL webserver is responding slowly due to the DOS.
If you want to look up a listing without using the Spamhaus website you can use the “host” or “dig” command line tools. To do this reverse the digits in the IP address and append zen.spamhaus.org on the end.
So for the IP 10.11.12.13 you would query 13.12.11.10.zen.spamhaus.org

Read More

Spamhaus dDOS

I got mail late last night from one of the Spamhaus peeps telling me that they were under a distributed Denial of Service (dDOS) attack. This is affecting email. Incoming email is delayed and they’re having difficulty sending outgoing email. This is affecting their responses to delisting queries.
They are working on mitigation and hopefully will be fully up and running soon.
Updates when I get them.
Update (8/29/2012): mail to Spamhaus should be back.

Read More

Questions about CAN SPAM.

In the US, the law governing the sending of commercial email is CAN SPAM. I’ve seen a number of questions about CAN SPAM recently.
One came from twitter, where someone was asking if just having an email address meant permission to send to it. Clearly, just being able to dig up an email address doesn’t imply permission to send marketing or commercial email to it. I can promise you April23@contact.wordtothewise.com did not sign up to receive information on increasing Facebook followers.
CAN SPAM doesn’t prohibit unsolicited email. All it says is that if you send unsolicited email you must do a few things.

Read More