SAN FRANCISCO (AP) - The dreaded Conficker computer worm is stirring. Security experts say the worm's authors appear to be trying to build a big moneymaker, but not a cyber weapon of mass destruction as many people feared.

As many as 12 million computers have been infected by Conficker. Security firm Trend Micro says some of the machines have been updated over the past few days with fake antivirus software - the first attempt by Conficker's authors to profit from their massive "botnet."

Criminals use bogus security software to extort money. Victims are told their computers are infected, and can be fixed only by paying for a clean-up that never happens.

Conficker gets on computers through a hole Microsoft patched in October. PCs set up for automatic Windows updates should be clean.

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