New Variants Of Cell-Phone Worm Appear

Security companies are warning that several new--and more dangerous--versions of the Cabir cell-phone worm have surfaced.

Earlier versions of the worm, discovered in June and spread through Bluetooth, were flawed in the way they propagated, which helped to slow the number of infections, says Mikko Hypponen, director of antivirus research for F-Secure Corp.

Since then, attackers have continued to work to enhance the worm. In November, virus writers tried to boost the spread of Cabir by piggybacking it with the Skulls cell-phone Trojan. This week, three versions of Cabir appeared, all of which target mobile phones with the Symbian Series 60 operating system and have their Bluetooth settings at "discoverable." For a more detailed discussion of the Cabir threat, click here.

Antivirus firms say the source code of the original Cabir worm and that of its new variants are extremely similar, which could mean the source code has been released and is circulating on the Internet.

So far, there have been no reports of the new Cabir variants successfully infecting cell phones. Says Hypponen: "The problems with cell-phone viruses are still small, but they're growing."