Last year word broke of a computer virus that had managed to slip into Iran’s highly secure nuclear enrichment facilities. Most viruses multiply without prejudice, but the Stuxnet virus had a specific target in its sights–one that is not connected to the Internet. Stuxnet was planted on a USB stick that was handed to an unsuspecting technician, who plugged it into a computer at a secure facility
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Hacking the Lights Out: The Computer Virus Threat to the Electrical Grid (preview)