A new type of computer worm which targets instant messaging (IM) clients has been identified by Kaspersky Labs.

Generically named by Kaspersky as Im-worm.win32.Zeroll, four variants of this Windows OS-based malware have been identified. The worm targets a range of popular IM clients, including Live Messenger, Google Talk, ICQ, Skype, Yahoo Messenger and even the XFire client used in online gaming.

Once a client has been infected with these worms, IT Pro News reports that the malware searches the contact list before sending a message to all the addressees on the list, pretending to be a message from the account associated with the client. This message contains a link to a website hosting an image that is invariably another malicious file, which in turn infects the recipient if they have insufficient security.

Multi-lingual worm

The worm is active around the world because it can send a message in one of 13 different languages as identified by the messenger client's settings and IP address. This helps mislead recipients with simulated conversation of a few sentences. According to Kaspersky, the worm is mainly active in Spanish or Portuguese speaking regions such as Mexico, Brazil, Peru and the US. However, it is also spreading across Europe - predominantly in Spain - as well as Africa and India.

"They are infecting as many machines as they can in order to get good offers from other crooks for such things as pay per install, spam and so on," said Dmitry Bestuzhev, the cyber security firm's regional expert for Latin America. He says that those behind the worm are creating a malware asset, leaving a backdoor in each computer open to exploitation by hackers and providing new vectors for further cybercrime.

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