Security experts have said that Stuxnet's complex design and its intent to hijack SCADA industrial control systems indicates that it was almost certainly the work of a state-backed group of programmers, while the large number of infections in Iran hinted that it was the most likely target.
None of those suspicions have been confirmed by researchers who have poured over Stuxnet's code, although some have spotted clues that either point to Israel or to an attempt by the hackers to pin blame on the country.
Stuxnet, which was first launched in June 2009 but didn't pop into public view until a year later, has been described as "groundbreaking" for its ability to infiltrate networks, sniff out SCADA systems and reprogram the hardware controllers that monitor and manage machinery in factories, power plants, pipelines and military installations.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed . His e-mail address is firstname.lastname@example.org .
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