Mosquito Trojan affects Symbian mobile phones, Sophos reports

Sophos Press Release

Mobile users hit by the Trojan may be stung by an expensive phone bill

Some versions of the Mosquitos game attempt to send expensive SMS text messages.

Experts at Sophos have advised customers not to panic, following media reports of a Trojan horse that affects cell phones, making them send text messages to premium rate numbers.

The Mosqit Trojan horse is written specifically to work on the Symbian operating system running on a Nokia Series 60 compatible device. The Trojan has been posted on a number of websites and peer-to-peer networks.

Hidden inside the Trojan horse is the following message:

This version has been cracked by SODDOM BIN LOADER No rights reserved. Pirate copies are illegal and offenders will have lotz of phun!!!

"If run on a cell phone this Trojan attempts to send expensive SMS text messages to premium rate numbers," said Graham Cluley, senior technology consultant for Sophos. "This hacked version of the Mosquitos game has an unpleasant sting in its tail. Whether your computer is on your desktop, or sitting in your jacket pocket, you should always exercise great caution about what you install."

Mosquitos game
The Mosquitos game runs on the Symbian operating system.

The Trojan, which is disguised as a cracked version of a game called "Mosquitos" can be installed onto modern smartphones, only after the user has seen several warnings about the possible dangers of installing unsigned applications.

"Obviously the discovery of a Trojan horse that can send expensive SMS text messages is going to generate interest in the media, but it's important to remember that the biggest virus problem remains on conventional desktop Windows PCs which are regularly assaulted by worms via the internet." continued Cluley.

More than 100 million users in 150 countries rely on Sophos’ complete security solutions as the best protection against complex threats and data loss. Simple to deploy, manage, and use, Sophos’ award-winning encryption, endpoint security, web, email, mobile and network security solutions are backed by SophosLabs - a global network of threat intelligence centers. Sophos is headquartered in Oxford, U.K., and is publicly traded on the London Stock Exchange under the symbol “SOPH.” More information is available at