Forensic research into the Stuxnet virus has determined that it in fact is designed to send enrichment centrifuges wildly out of control. As to where it originated, this article only says that Israeli government officials get broad smiles when they talk about how much damage it has probably caused to Iran's nuclear program.

Apparently the Iranians have had hundreds of their centrifuges self destruct.

The story of this would make super spy George Smiley smile.