by Dan Goodin
Researchers have uncovered a never-before-seen version of Stuxnet. The discovery sheds new light on the evolution of the powerful cyberweapon that made history when it successfully sabotaged an Iranian uranium-enrichment facility in 2009.
Stuxnet 0.5 is the oldest known version of the computer worm and was in development no later than November of 2005, almost two years earlier than previously known, according to researchers from security firm Symantec. The earlier iteration, which was in the wild no later than November 2007, wielded an alternate attack strategy that disrupted Iran's nuclear program by surreptitiously closing valves in that country's Natanz uranium enrichment facility. Later versions scrapped that attack in favor of one that caused centrifuges to spin erratically. The timing and additional attack method are a testament to the technical sophistication and dedication of its developers, who reportedly developed Stuxnet under a covert operation sponsored by the US and Israeli governments. It was reportedly personally authorized by Presidents Bush and Obama.
Source: Ars Technica