Rare worm hits Symbian mobiles, Windows PCs

F-Secure this week came across cross-platform malware, seemingly capable of jumping from a mobile device to a Windows PC and back.

The worm, which the Helsinki-based anti-virus firm is calling "Mobler," can move between Symbian and Windows platforms - doing most of its damage on the PC side.

While infecting a mobile device, the worm copies itself to a memory card and then tries to dupe affected users into infecting their PCs, according to a post on F-Secure's blog by Mikko Hypponen, chief research officer.

The malware poses no threat to mobile users in its current form, according to F-Secure, but it could be the basis for future malware.

And while it does not have a spreading mechanism, it creates a Symbian installation package that inserts a Windows executable that's visible as a system folder in Windows Explorer.

Hypponen said today that worm, sent to F-Secure by an affected end user, is something his company had been expecting. It is not widespread, he said.

"We were waiting for this to happen quite a while ago, because it seems to be a pretty large infection route," he said. "Although this is the first virus that's trying to do this, this is pretty simple that it's copying itself to network drives. If it were to use email it would spread much more widely."

Dave Cole, director of Symantec Security Response, said today that crossover malware is following the surge in personal devices.

"It's not something we'd coin as an epidemic. But we are seeing malware out there that are being created that cross over from platform to platform," he said. "There's going to be a lot of personal technology out there, and there are bound to be some malware testing the boundaries."