From Wired’s Threat Level:

Researchers at Russia-based Kaspersky Lab discovered that a part of the module that allows Flame to spread via USB sticks using the autorun function on a Windows machine contains the same code that was used in a version of Stuxnet that was unleashed on computers in Iran in 2009, reportedly in a joint operation between the United States and Israel. The module, which was known as Resource 207 in Stuxnet, was removed from subsequent versions of Stuxnet, but it served as a platform for what would later develop into the full-fledged Flame malware that is known today.