Cloudflare and Spamhaus

Spamhaus has been the subject of a lot of discussion the last few weeks. I touched on this a little in June when I blogged that a number of large brands were getting SBL listings.
But big brands are not the only companies with publicly discussed SBL listings.
Cloudflare, the content delivery network that grew out of project honeypot, has a number of SBL listings, covering at least 2 /18s and a /20. Representatives and customers of Cloudflare have been discussing the listings on twitter.
As a content provider, Cloudflare isn’t actually sending mail nor are they actually hosting the content. What they are doing is providing consistent name service and traffic routing to malicious websites. In fact, they’ve been providing services to a malware botnet controller (SBL138291) since May, 2012. They’re also providing services to a number of SEO spammers. Both of these actions are justification for a SBL listing, and Spamhaus has a history of listing providers protecting spammers.
Cloudflare claims they take action on all “properly filed complaints” and they may actually do that. But their reports require quite a bit of information and require consent for releasing information to 3rd parties. Looking at the website, it appears to me to be a site designed to discourage abuse reports and stop people from reporting problems to Cloudflare.
When you look at the Cloudflare business model it’s clearly one that will be abused. Cloudflare acts as a reverse proxy / pass through network that caches data from their customers. This protects the abusers webhosting setup and prevents people tracking the abuser from being able to determine the true host of a website. As a responsible internet citizen, Cloudflare should be disconnecting the customers hiding behind Cloudflare’s services.
Unfortunately, Cloudflare seems unwilling to actually police their customers. They’ve taken a totally hands off approach.
Let’s be frank. Cloudflare has been providing service to Botnet C&C servers for at least two months. It doesn’t matter that the abuser has the malware on a machine elsewhere, Cloudflare’s IP is the one that serves the data. I don’t care what you think about spam, providing service to malware providers is totally unacceptable. It’s even more unacceptable when you claim to be a security company. Nothing about malware is legitimate and the fact that Cloudflare is continuing to host a malware network command and control node is concerning at the very least.
Cloudflare (.pdf) is listed on Spamhaus for providing spam support services. The most obvious of these is providing service to a malware controller. And Spamhaus escalated the listings because they are allowing other abusers to hide behind their reverse proxy.

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If you run Windows and you haven’t yet checked to see if you’re infected, you should do so soon. There are a number of websites you can visit that will tell you if you are actually infected with the DNS changer virus and if you are will give you information on how to fix your system.

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Browsers, security and paranoia

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Another participant told me he thought my recommendation to not use a windows machine to browse the web was over the top and paranoid. It may be, but drive by malware attacks are increasing. Visiting big sites may not be enough to protect you, as hackers are compromising sites and installing malware to infect visitors to those sites. Some ad networks have also been used to spread malware.
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Avoiding the internet from a machine running Windows is a security recommendation I don’t expect many people to follow, but I do not think security and anti-virus software is enough to protect people from all of the exploits out there.
Of course, there are a lot of reasons that one might be forced to use a particular browser or operating system. For instance, I was on the phone with my bank just today to ask if they supported Safari. They say they do, but there are some things that just don’t work. The customer service rep said that they recommend Internet Explorer to all their users. She then suggested I switch browsers. No thanks, I’ll deal with the broken website.
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