Malware authors must have a soft spot in their hearts for the long-maligned South African vuvuzela, because once again, the most annoying noisemaker in World Cup history is driving people to Web sites which push infections down to their computers. This time, people are retweeting the malicious links attached to a message that reads “OMG! Vuvuzela banned!” along with the hashtags #worldcup and #vuvuzelabanned. At last check in Google, references to the malicious links number over 16,000.
The tweets use a variety of different link shortening services (including bit.ly, tinyurl.com, is.gd, and dr.tl) to mask the fact that their destination is actually a bogus image hosting website hosted on the .in top-level domain (supposedly used by Web sites registered in the country of India, but these sites are all hosted elsewhere). The Web site you eventually land on calls itself Image Sheep, while in the background, your PC is being herded into a botnet.
As an aside, there is a real image hosting service by the same name, but the real Image Sheep is registered elsewhere and hosted in an entirely different network than these fake Image Sheep clones.
Once the victim’s browser loads the fake Image Sheep page, it pushes a Java “image viewer” applet, named target.jar, down to the browser. It’s easy to pick apart the contents of this file, which contains additional Java applets and PHP scripts that push the malicious file (named IMG12523.jpg.exe) down to the victim’s computer. The file itself is a downloader component of an adversary we’ve seen before: Trojan-Backdoor-Protard (aka Gootkit), which retrieves additional malware and retrieves complex instructions.