A new variant of the Koobface worm has returned to menace users of Facebook. As before, the malware generates messages to friends of infected users on the social networking website. These messages direct the unwary into visiting websites that supposedly offer video clips. Would-be marks are told they need the latest copy of Adobe Flash to view this content and are prompted to download a file, which actually contains the worm's payload.
If the code executes on a vulnerable Windows PC the user gets infected. The worm's lifecycle then begins anew, ready to target their Facebook friends too. The malware was first spotted in late July.