Google Docs used in latest spam attack
Spammers find legitimate way to evade corporate and desktop spam filters.
Spammers will do just about anything to get their e-mail through corporate and desktop filters. According to MessageLabs, they're now using Google Docs, a perfectly legitimate way to publish to the Web. Only what they're publishing is the same old wares--this time, it's enhancement pills. This week I talked with Matt Sergeant, senior anti-spam technologist with MessageLabs, who told me how they they've tracking one Google Doc since May 8, 2008.
Later in the conversation, Sergeant talks about the resurgence of Storm. Only a few weeks ago, MessageLabs reported a notable decrease in computers infected with the Storm botnet.
Below is a transcript of part of my interview. The entire podcast can be heard here.
Matt Sergeant: What's happening with Google Docs is that Google Docs is a way to publish your documents online. So, for example, word processing documents and spreadsheets and so on, and much like if you were using Microsoft Word you can embed links within those documents. What this does for the spammers is it allows them to effectively publish online a Web page on hosting sites such as Google that has all the bandwidth in the world for hosting it, and it's also a Web site that is never going to get blacklisted by anyone because nobody would be stupid enough to blacklist Google. So in effect, for the spammers this is a human shield effect. They can host their information and links online on a very stable source of bandwidth and links, and not worry ever about it being taken down or blacklisted.
Me: When did you first see this happening?
Sergeant: The first one that we saw, which showed on our radar in extremely small numbers clearly as a test by the spammers, was on May the 8th. So I guess that's about two weeks ago now.
Me: Have you contacted Google?
Sergeant: We've contacted Google, and also there's a link at the bottom of each one of the documents that Google publishes online that says, "Report this as spam." We clicked that link and I imagine anyone else who got the e-mail clicked that link as well. Unfortunately, Google has proved themselves to be quite slow at tackling this kind of abuse. Weeks later this document is still available online despite the reporting as spam.
Me: When you say that Google has a history of this can you site another example in recent memory where they've been slow to act on spam like this?
Sergeant: Generally, yeah there's a couple of different issues that we see in spam with Google. The first and very obvious one is spam directly from Gmail accounts, often that's the Nigerian spammers who are sending out these offers of millions of dollars where there is in fact no money. By most people's standards, Google tends to be quite slow at shutting down those accounts, whether it be an account that's actually an e-mail or just a drop box account for people to reply to. So those accounts seem to stay active for longer than if they were being hosted somewhere else for example. The other thing we see with Google is redirector links, so they have these links on their Web site which allow anyone or just about, but obviously mostly the spammers to have a link that looks like it's going directly to Google, but in fact after you've visited Google it redirects you to the actual spammers Web site. These redirectors are quite common on loads and loads of Web sites out there, but obviously again they're gaining advantage from Google of all the bandwidth and unblock ability of the Google Web site.
Me: So give me an example of what we would see if we went to the spammers website, what sort of, where is it being hawked or Malware being served up.
Sergeant: In the example that we saw on May the 8th it was a very simple pills scam or a pills Web site. So the e-mail came in with a link to Google Docs and very little of a text in the e-mail itself. They're very hard to block because there was very little to go on regarding the contents of it. When you went to the Google Docs Web site you saw much more information about the pills available for sale and the prices and so on, and almost every bit of text within that was a link which took you to the spammers drop Web site, which is where you would actually go if you wanted to purchase some of those pills.