Currently, Linux-fueled iPods are a very small minority because they require users to do the system swap. The malicious program, called Podloso, might not present a real threat, but Kaspersky noted that it does demonstrate that it is theoretically possible to create malicious programs for devices such as the iPod.

Podloso is a typical "proof-of-concept" virus, which is created in order to demonstrate that it is possible to infect a specific platform. Although some users might find it odd that security researchers would ever whip up a virus, the type of concept code developed by Kaspersky is very common, and considered a preventative measure against future threats.

Concept Driven

Some concept code is prescient of new attacks. For example, the first proof-of-concept viruses for mobile phones began appearing a few years ago, and now there are several hundred phone viruses that exist.

But Podloso is not likely to become a real threat in the near future, security analysts have noted. The Podloso virus only affects iPods running Linux, and it does not copy itself automatically from one iPod to another. Users would have to install the virus manually to another iPod, and the virus does not spread from the devices to PCs.

However, Ron O'Brien, senior security analyst at security firm Sophos, said that with the increasing popularity of media players such as the iPod, as well as smart phones and PDAs, there are likely to be more threats geared toward these devices in the future.

Even USB drives are subject to infection. They can have a virus embedded into their system that launches when a user plugs them in.

Plug and Play

"People tend to forget any type of mobile device can contain malware, even the USB you got at a trade show," he said. "Users tend to see them just as a storage device, and plug them in without scanning for malware."

With the iPod, it should become a fairly standard procedure for a computer to scan the device before using it to make sure it has not been infected. O'Brien noted that even though the recent iPod issue affects a very small number of users, and is not spreading, it is simply a good security practice to scan all devices when they are first attached to a computer.

"These security practices are recommended for any peripheral device, even CDs and external hard drives," he said. "It's better to be overcautious than get hit with malware."