Microsoft puts the kibosh on Facebook worm Koobface

Computerworld - Microsoft Corp. is trying to stamp out the Koobface worm, which has spread aggressively on social networking sites such as Facebook and MySpace, the company said yesterday.

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 to users every month on Patch Tuesday.

Koobface, which first appeared in May 2008, struck Facebook again just last week, with researchers at Trend Micro Inc. tracking its romp through the service. According to Trend Micro researcher Jamz Yaneza, the new Koobface.ac variant 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, and then using the cookies to log into 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 Web sites."

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 ones 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, the 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.

Read more about Malware and Vulnerabilities in Computerworld's Malware and Vulnerabilities Topic Center.