F-secure spots trojan that infects both cell phones and PCs

Security firm F-Secure has discovered the first virus that targets both smartphones and PCs. The virus is called Cardtrap.A and is a trojan that attacks Symbian-based smartphones. But when users insert the phone's memory card into their computers the virus will try to infect the users' PCs.

Although this virus is only a small threat because it requires user interaction and can't infect a number of Windows systems, including Windows XP, F-Secure says it may indicate that more advanced viruses designed to infect both cell phones and PCs may arrive in the near future.

Cardtrap.A is a malicious SIS file trojan, which tries to disable large number of system and third party applications and installs Windows malware on the phone memory card.

The Cardtrap.A installs Windows worms Win32/Padobot.Z and Win32/Rays to the phone memory card.

The Padobot.Z is copied along with autorun file that points to the Padobot.Z executable, so that if the card is inserted into PC using Windows the autorun tries to execute Padobot.Z.

We tried this feature with Windows XP SP2 and Windows 2000, and could not get autorun to work. But the autorun feature might work with some Windows installations.

The Win32/Rays is copied with name System.exe and has the same icon as System folder in the memory card. So that if user is trying to read the contens of card with PC he might accidentally execute the Win32/Rays.