Viruses/Worms News

Koobface worm grows more sophisticated in web 2.0 attacks

Tuesday, August 11, 2009

Web security researchers are warning that the notorious Koobface worm that spreads on social networks like Facebook and Twitter has grown more sophisticated in order to evade detection and trick more savvy users into downloading malware.

The malware writers have relied on the proliferation of link sharing on social networks to spread the Koobface virus. Koobface sends out spam messages from hijacked user accounts containing malicious links to websites where users are prompted to download Trojan malware and phony antivirus software.

Kaspersky labs reported that the spam messages are now becoming more realistic, with different Koobface spam messages featuring random additions like "HA-HA-HA!" or "LOL," while the malicious URLs are better disguised through a different bit.ly shortened URL each time.

Although it was originally designed to propagate through Facebook and MySpace, Koobface now spreads througho eight other social networking sites, including Twitter, thanks to a program that steals a user's cookies from the social websites he or she has visited, Trend Micro reported.

Koobface can also install other types of malware on an infected PC, which makes it valuable to other cybercriminals who appear to be renting out the Koobface botnet of infected machines to install malware for data theft, search hijacking and selling rogue antivirus software.

Koobface also has a way of tricking users into breaking CAPTCHA images for it in order to spam a user's contact list.