Microsoft is trying to stamp out the Koobface worm, which has spread aggressively on social networking sites such as Facebook and MySpace, the company said Tuesday.
In a post to the company's malware protection center blog, researcher Scott Molenkamp said that definitions for Koobface have been added to the Malicious Software Removal Tool (MSRT), the free anti-malware utility that Microsoft automatically delivers every month to users on Patch Tuesday.
Koobface, which first appeared in May 2008, struck Facebook again just last week when researchers at Trend Micro Inc. tracked its romp through the service. That new Koobface.ac variant, said Trend researcher Jamz Yaneza, tries to trick users into downloading a bogus update to Adobe System Inc.'s Flash, and spreads by hijacking browser cookies to 10 different social networking sites, then uses the cookies to log in to accounts and spew out more fake messages to friends.
According to Molenkamp, the MSRT update targets a wide range of components that fall under the Koobface category. "This family is not just a worm, but a collection of different components that can each perform a different task," he said. "These include downloading, Web hosting, password stealing, displaying pop-ups and sending messages to contacts on various social network websites."
MSRT can now seek and destroy Koobface components aimed at users of bebo.com, Facebook, Friendster, fubar.com, hi5.com, LiveJournal, MySpace, myYearbook, Netlog and Tagged. Those sites are the same that Koobface.ac targets when it pilfers browser cookies.
Microsoft has had some success in cleaning infected PCs with the MSRT. Last November, for example, the company crowed that the tool had purged nearly a million machines of phony antivirus software, dubbed "scareware," in just nine days. In June 2008, MSRT sniffed out 1.2 million PCs infected with a family of password stealers, while in February, it scrubbed the Vundo Trojan horse from about a million machines. During several months at the end of 2007, the tool hit the then-notorious Storm Trojan horse, eradicating it from about a half-million PCs.
The MRST can be downloaded manually from Microsoft's site, or retrieved via the Windows Update service.