This is weird - and a little troubling.

It's not as bad as it could be - they think. They can't detect the information being gathered - keystrokes from drone operators - being sent to an outside location. But the question of how the virus got into the system in the first place is still a mystery.

PC World:

The computers used to control Predator and Raptor drones used in Afghanistan and other war zones have been reportedly infected by a virus that captures the keystrokes of the pilots operating the unmanned aircraft.

Although detected two weeks ago by the military's network security systems, the military has been unable to purge its computers of the apparent keyboard logger, Noah Shactman reported Friday in Wired's Danger Room blog.

"We keep wiping it off, and it keeps coming back," a source familiar with the network infection told Shactman. "We think it's benign. But we just don't know."

According to the report, the virus hasn't prevented pilots stationed at Creech Air Force Base in Nevada--where the drone control center is located--from completing their missions. Nor has any classified information been lost or sent to an outside source, Wired reported.

No one knows how the malware got into the system or whether its arrival was deliberate or accidental, but it has infected both classified and unclassified machines. That means information nicked from the classified networks could be funneled to the unclassified networks where it could be leaked to clandestine locations on the public Internet.

[...]

Although the keylogger appears to be harmless, some security experts found news of the intrusion alarming.

"This is bad in so many ways," Richard Stiennon, chief research analyst with IT-Harvest in Birmingham, Mich., told PCWorld. "It indicates that the military is using completely insecure operating systems and practices for the critical function of controlling drones."

"These are deadly weapons that must work as required and only when required," he continued. "To have their command and control corrupted by apparently common malware is inexcusable."

Um, yeah. What he said.