Internet Storm Center on the Spamhaus DOS

The Internet Storm Center (ISC) has a blog post up discussing the DOS attack against Spamhaus. They do confirm they saw traffic approaching 300Gbps against Spamhaus. They also point out that most people probably never knew.

The attack was significant, but not globally so despite the media reports to the contrary. When news of the attack reached the Internet Storm Center, we did have a brief moment of panic and contemplated resorting to cannibalism. However, we quickly decided against this option (due to a combination of calmer heads prevailing and a lack of consensus on whether people could be turned into bacon).

ISC has a lot of technical details about how to secure your DNS servers, and I strongly encourage everyone to go look and make sure their DNS servers are secure. I checked ours a few days ago. I really didn’t think they would be open; Steve gets DNS and keeps up with security so it was unlikely we had open resolvers. I looked up our resolvers anyway because a second pair of eyes on things is never a bad thing.

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Spear phishing

It’s been about a year since people started publicly talking about spear phishing attacks against ESPs and major emailers. There was a lot of energy put into talking about how to protect against future attacks. I have to wonder, though, how much of that talk translated into action?
What processes do you have in place to protect your company against attacks?
If you’re at an ESP, do you have the ability to scan your outgoing stream for keywords or domains?
If you’re a brand, have you implemented restrictions on which employees have access to your databases?
What have you done since the last set of attacks? Are you vulnerable if new attacks start?
More information on ESP attacks:
Be on the lookout
Time for a real security response
Email attacks

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Spamhaus answers about the recent DoS attack

Answers about recent DDoS attack on Spamhaus

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Troubleshooting tools

There have been a number of comments on my post about Hotmail moving to SPF authentication having to do with troubleshooting authentication failures. I have been helping clients troubleshoot these issues, and am able to take on new clients to solve authentication problems. Contact me for more information.
Of course, many of these issues can be solved with access to the right tools. Steve’s been working on a number of tools that may help the troubleshooting process and we’ve recently launched them on Emailstuff.org. The website itself contains a number of DNS and data related tools we use for investigations and thought we’d share with the public at large.
One of the really useful tools is the SPF record expander. Plug in any domain, like google.com, and see what IP addresses they authorize to send mail.

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