On social networking sites like Twitter, Facebook and MySpace, if someone says to you ”Is it you in this video?,” be warned, because in reality, it leads to a fake YouTube page with a thumbnail which when clicked checks you OS version, downloads a Java applet called jnana.tsa on Linux and exploits a Remote Code Execution vulnerability in outdated versions of Java. Once installed on a computer, the worm hijacks the social networking accounts of its owner and uses them to propagate.
The applet is dropped inside the user’s home directory and stops running at computer reboot. This means that on Linux, unlike on Windows, the Koobface infections are temporary. Which means if you happen to get that infection, reboot immediately.
This shows that Linux and Mac OS X users aren’t vulnerable to malware, as their market share increases they will become an attractive target for social networking worms like Koobface.