“New and important evidence found in the sophisticated ‘Stuxnet’ malware targeting industrial control systems provides strong hints that the code was designed to sabotage nuclear plants, and that it employs a subtle sabotage strategy that involves briefly speeding up and slowing down physical machinery at a plant over a span of weeks.

‘It indicates that [Stuxnet’s creators] wanted to get on the system and not be discovered and stay there for a long time and change the process subtly, but not break it,’ says Liam O Murchu, researcher with Symantec Security Response, which published the new information in an updated paper (.pdf) on Friday.”

(Source: Clues Suggest Stuxnet Virus Was Built for Subtle Nuclear Sabotage | Threat Level | Wired.com.)