Security firm F-Secure has said the security challenges in the mobile environment are becoming quickly similar to the problems encountered in the PC world and the cost to users is rising. Some of the malware attacks which occurred in 2004 include:

• In spring 2004, a trojanized game called Mosquitos was found. It secretly sent messages to expensive toll numbers, creating invisible costs for the user.
• June 15th: Cabir worm was found. Cabir is a worm that replicates over-the-air using bluetooth connections.
• June 16th: Cabir.B is found. This new variant had minor differences compared to the original.
• During the autumn, Cabir.B started spreading in the wild. It has been detected in several countries since, including China, India, Turkey, Philippines and Finland. It continues spreading today, traveling from one country to another as people with infected phones travel.
• November 19th: Skulls.A trojan is found. It replaces icons on the phone with skull images, making the phone almost useless.
• November 29th: Skulls.B is found.
• December 9th: Cabir.C is found.
• December 9th: Cabir.D is found
• December 9th: Cabir.E is found..
• December 21st: Skulls.C is found.
• December 21st: Cabir.F is found.
• December 21st: Cabir.G is found.

This last batch of malware was distributed masked as a pirate version of a popular game for mobile phones and, when run, installs Skulls and Cabir variants and tries to attack security products installed on the phone.

F-Secure noted that in the future, it is likely there will be new kinds of attacks -- trojan horses in games, screensavers and other applications -- resulting in false billing, unwanted disclosure of stored information, and deleted or stolen user data.