Researchers at Symantec have identified an earlier version of the Stuxnet malware that shows that the cyberattacks on Iran's Natanz nuclear plant date back as early as 2005 and targeted another piece of uranium-enrichment equipment.

Symantec found what it calls Stuxnet version 0.5 of the sophisticated cyberweapon among the samples it had collected from the version of the malware that was first discovered in the wild back in July 2010, which was created in 2009. The newly detected version of Stuxnet was in action mainly between 2007 and 2009, according to Symantec. The cyberweapon malware was reportedly launched by the U.S. and Israel against Iran's nuclear facility to derail the possible development of nuclear weapons.