The base from which the US Air Force directs its ‘remote-killing’ drone aircraft has become infested with Trojans, Wired magazine has reported.

According to the story, an unidentified keylogger Trojan has infected the computer systems at Creech Air Force Base in Nevada used to fly the drones on missions over countries such as Pakistan and Afghanistan,  causing no operation problems but plenty of anxiety.

The Trojan has so far resisted attempts to remove it permanently, affecting both classified and unclassified systems at the base.

“We keep wiping it off, and it keeps coming back. We think it’s benign. But we just don’t know,” Wired quoted sources at the base as saying.

The extent to which the malware represents a major security threat will depend on the intention behind those who created it. It could be a piece of wayward commercial malware that somehow found its way on to military systems but it could also be a program designed specifically by an outside power to disrupt the drones.

No secret data is said to have been stolen but the report implies that the engineers at the base can’t be sure.

The chance of a PC keylogger directly disrupting drone control systems is vanishingly remote. Those systems will be isolated, both from base systems and from the Internet and they will not be running Windows.

It is more likely that the malware has infected other computers on the base. The Wired article refers to engineers resorting to instructions from Kaspersky when trying to remove the malware, which sounds incredible. The standard procedure for removing malware in high-risk situations is to wipe every affected drive and rebuild the system from scratch; the idea that conventional antivirus software might be needed hints that the computers affected might be less critical.

However, the mere association with security vulnerability at what has turned into one of the US’s most potent military systems will arouse cybersecurity worry. The drones have been used to target a wide range of militant enemies of the US, including the recent killing of Al Qaeda sympathiser, Anwar Al-Awlaki.