Facebook users have been under a sustained attack that attempts to install malware on their Mac- or Windows-based machines by luring them to salacious videos.
According to a blog post published early Wednesday by an F-Secure researcher, the attack spreads virally using the Facebook “Like” feature, in which users register their approval of pictures, video or other content. It's the first time malware has used such viral links, the researcher said.
The attack was already in its 16th hour when the post was published a little after 9 am GMT. Some 10 hours later, the attack appeared to be ongoing, using subjects such as “oh shit, one more really freaky video” and “IMF boss Dominique Strauss-Kahn Exclusive rape Video” as bait. According to Sophos Senior Technology Consultant Graham Cluley, blogged much later on Wednesday, the only thing that changed about the scam was the subject, which had morphed to promise a sex video of celebrities Rihanna and Hayden Panettiere.
As is all the rage right now in malware attacks, the Facebook scams are actively targeting Mac users. Those who take the bait see webpages that mimic an antivirus scan taking place on an OS X system that claims it has serious malware infections. When marks install the fake security software included in the ruse, they are compromised.
A Facebook spokesman said the company doesn't comment on specific attacks but went on to contradict himself by adding “we are in the process of investigating, blocking the links, and remediating any affected users.”
According to F-Secure, the attack may be harder than most for Facebook to repel because it uses the Like feature rather than links on a user's Facebook Wall, which are easier to filter.
When testing the attacks from IP addresses located in Germany, Finland, France, India and Malaysia, users were safely redirected to YouTube. Users with IP addresses based in the US and UK, however, were taken to sites offering the Mac scareware and Windows malware.
“The attack is GEO-IP as well as OS aware,” F-Secure warned. ®