Cyber criminals will focus their attention on PCs running Windows XP next year, says F-Secure.

According to the security firm, machines running Microsoft's older operating system will be the biggest security threat in 2012. Windows 7 may have become the most popular PC operating system in the world, StatCounter figures for October revealed Windows 7 runs 40.5 percent of PCs across the world, while XP can be found on 38.5 percent. However, it doesn't mean there'll be a dramatic decline of Windows XP just yet

According to Sean Sullivan, security advisor at F-Secure: "People seem to be adding new systems without necessarily abandoning their old XP machines, which is great news for online criminals, as XP continues to be their favourite target."

The security firm also revealed Windows Phone 7 devices would be targeted by online criminals in 2012.

"Windows developers should have an easy time creating apps for all current versions of Windows. All of these platforms make use of Microsoft's .NET framework, which makes apps easily portable between Windows 7, Xbox Live and Windows Phone 7," he said while also questioning whether "malware authors will eventually take advantage of this portability?" as well.

F-Secure also says the forthcoming version of Google's Android operating system, Ice Cream Sandwich, looks set to bring more innovative apps and increase the popularity of tablet PCs with consumers even more. However, it might not be long before the cyber criminals turn their attentions to tablet devices.

"There will be many interesting surprises in 2012's threat landscape, though some things will remain the same," added Sullivan.

"We don't expect a drop-off in Windows based threats just because other platforms are emerging. The market isn't just changing, it's growing. I have no doubt that some innovative criminal will find some way to exploit that growth."

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