Iran, a Lost Drone, and a Computer Virus - Lessons to be Learned

Did a computer virus infection result in Iran acquiring a United States recon drone?

In October, the major news outlets announced that the piloting systems used by unmanned recon drones in Afghanistan and other nearby countries was compromised by a virus capable of recording keystrokes or user authentication information.  The Air Force followed up with a press release that this virus was only a credential stealer, and was not designed to transmit or corrupt data, and that the systems were completely disconnected from the internet and that the malware was introduced through removable media.