Ah, the Great British summer. Rain, sporting excellence, and a huge surge in the number of zombie PCs.

According to the Shadowserver Foundation the past three months have seen a threefold increase in the number of hijacked 'zombie' PCs. And the Shadowserver Foundation should know - like Scooby and the gang, albeit with more organisation and fewer dogs, its mission is to track zombie numbers worldwide.

The Foundation believes that more than 450,000 computers are currently part of zombie networks, otherwise known as botnets. Criminals 'recruit' unsuspecting users' PCs to botnets in order to use them as a kind of unsanctioned computing cloud. Using such multiple PC resource, scammers can send spam email, launch attacks on websites and store stolen data - all without bringing any unwanted attention to their own machines.

Shadowserver believes that the increase in zombie PCs is linked to a flood of booby-trapped websites. It also marks a move away from more traditional methods of attack. And here's some juicy grist for the Mac/Linux mill - almost all zombie PCs are Windows based. (But then, so are almost all PCs.)

Although PC zombies share few similarities with their undead human brethren, a stake through the heart of each solves the problem - albeit with terminal side effects.

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