If you are a user on the most popular networking site, Facebook, you have to be chary if someone sends you a video or an invitation to a group. Many Facebook users have already been fallen preys for Koobface, a virulent virus that is spread through Facebook. It is transmitted through a video, which will prompt the users to download a seemingly innocuous stuff. However, what you will download is a baleful malware that will harms your computer.

Now it is reported that the virus has also attacked shared videos on Google Reader RSS Feed and on Picasa, a popular photo-sharing website backed by Google. However, analysts say that it is hard to expurgate this virus because it has hijacked the user’s computers and therefore it can only be wiped out by the user himself. This conundrum has also sparked a discussion of whether Facebook’s business will be adversely affected just because of this simple yet dangerous virus.