Hackers Hijack PC’s for Sex Sites

[M]ore than a thousand unsuspecting Internet users around the world have recently had their computers hijacked by hackers, who computer security experts say are using them for pornographic Web sites.

The hijacked computers, which are chosen by the hackers apparently because they have high-speed connections to the Internet, are secretly loaded with software that makes them send explicit Web pages advertising pornographic sites and offer to sign visitors up as customers.

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Computer owners can protect themselves by using firewall software or hardware, which prevent unauthorized entry and use of computers, Mr. Smith said. The rogue program does not affect the Apple Macintosh line of computers or computers running variants of the Unix operating system.

So what operating systems are affected?