The Moscow-based security firm credited with solving various mysteries around Stuxnet and Duqu today announced the discovery of Flame, a data-stealing virus said to have lurked on thousands of computers in the Mideast for as long as 5 years. A Kaspersky Lab spokesperson described it in a Reuters interview as "the most complex piece of malicious software discovered to date."

Adds Bruce Sterling, "Given that this has been out in the wild for a couple of years now, what's five times bigger than 'Flame' and even less understood?"

Writing today at Wired News, Kim Zetter reports that Flame is believed to be "part of a well-coordinated, ongoing, state-run cyberespionage operation."

Kaspersky has a FAQ about Flame, here.

(Image: Kaspersky Labs)