THINK twice before uploading your holiday pictures to Facebook - you could be helping someone to steal information from your computer. A botnet called Stegobot was created to show how easy it would be for a crook to hijack Facebook photos to create a secret communication channel that is very difficult to detect.

Like most botnets, Stegobot gains control of computers by tricking users into opening infected email attachments or visiting suspect websites. But rather than contacting the botmasters directly, it piggybacks on the infected user's normal social network activity. "If one of your friends is a friend of a friend of the botmaster, the information transfers hop by hop within the social network, finally reaching the botmasters," says ... Read more »