The Flame virus discovered last week targeting computers in Iran has been ordered to self-destruct, leaving no trace - and no indication of who created it.
While the 20MB behemoth contained a Suicide self-destruct module, its creators for some reason decided not to use this. Instead, they used a separate removal tool, browse32.ocx, downloaded from a command and control server still under the control of the attackers - a risky move, given the likelihood of detection.