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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News about the Rustock takedown

Spam levels plummeted 2 weeks ago as the Rustock botnet was beheaded. Reports have been trickling out in the press about the takedown, about the botnet and about the team responsible.
Rustock Takedown Analysis at The Register
Brian Krebs’ intitial report of the takedown
Taking down botnets from a Microsoft attorney
Spam Network Shut Down at the Wall Street Journal
Global Spam Levels Graph from Symantec
 

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Browsers, security and paranoia

MAAWG is coming up and lots of us are working on documents, and presentations. One of the recent discussions is what kind of security recommendations, if any, should we be making. I posted a list of things including “Don’t browse the web with a machine running Windows.”
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.
Criminals have even figured out how to install malware on a machine from email, without the recipient having to click or open attachments.
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.
Compromises are a major threat, and criminals are spending a lot of time and money on creating ways to get past current security. No longer is “not clicking on malware” enough to protect users. When a security clearinghouse is compromised and used as a vector for a targeted attack against Google, none of us are safe. When a security company is compromised, none of us are safe.
I realize my recommendation to avoid browsing the web on a Windows based machine is more wishful thinking than practical. I also know that other browsers and operating systems will be targeted if enough people move away from currently vulnerable operating systems. And I know that a simple, offhand suggestion won’t fix the problem.
As someone who’s been online long enough to see the original Green Card spam I know that online dangers evolve. But I can’t help thinking that most of us aren’t taking the current threats seriously enough.

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Uptick in botnet spam

There’s been a heavy uptick in botnet spam over the last few days, judging by things I’m hearing and my own mailboxes. There are a few common subject lines, but all of them are trying to get recipients to either run programs or visit malicious web pages.
The first subject line I’m seeing a lot of is “<name> wants to be friends with you on facebook!” In my mailbox most of those names have not been common European names. The give away that this isn’t actually a Facebook invite is the Reply-To address pointing to Linkedin. The URLs in the message appear to be random strings of numbers, and may actually encode recipient information in them.
The second has a subject that that is a variation on “End of July Statement.” The spammers are mixing capitals, adding in “Re:” and “FWD:” and sometimes increasing the urgency by adding required or STAT!! to the mail. These mails contain a .zip file which probably contains some virus which will turn the recipient machine into the next spam spewing bot.
The third variation has the subject line “Uniform Traffic Ticket.” The content is a citation that tells the recipient they were speeding somewhere in New York (possibly other states, I have only done a spot check of the couple hundred copies I have). There is, however, a .zip attachment with a virus.
Most people probably aren’t seeing these. SpamAssassin is doing a reasonably good job here of catching the spam and filtering it. I’m sure that the bigger ISPs are also filtering it effectively. But one person did forward a copy of the spam to a mailing list and ask if anyone knew what was going on.
If you get any of these messages, you don’t need to ask. It’s virus spam. Don’t open it and don’t forward it.

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