Fortunately, the worms are unlikely to spread very far. "They don't spread quickly because they're not purely autonomous," said Ollie Whitehause, a researcher with Symantec. Unlike worms on computers, the Trojan horses hitting cell phones spread as attachments that require users to download them.
Nyxem is the PC worm. Unlike the mobile phone malware, Nyxem is spreading rapidly and carries a potentially destructive set of instructions.
Also nicknamed the Kama Sutra worm, it is programmed to overwrite all of the files on computers it infects on 3 February, said Mikko Hypponen, chief research officer at F-Secure Corp.