Insurgents in Iraq have hacked into live video feeds from Predator drones, a major weapon in a Pentagon spy system that serves as the military's eyes in the sky for surveillance and intelligence collection.
Although militants could see the video, there is no evidence they were able to jam the electronic signals from the unmanned aerial craft or take control of the vehicles, a senior defence official said Thursday, speaking on condition of anonymity to discuss sensitive intelligence.
Obtaining the video feeds can provide insurgents with critical information about what the military may be targeting, including buildings, roads and other facilities.
Shiite fighters in Iraq used off-the-shelf software programs such as SkyGrabber, available for as little as US$25.95 on the internet, to capture drone video feeds regularly, the Wall Street Journal reported. The hacking was possible because the remotely flown planes had unprotected communications links.
The defence Department has dealt with the problem, first discovered a year ago, and is working to encrypt all its drone video feeds from Iraq, Afghanistan and Pakistan, defence officials said.
One defence official noted that upgrading the encryption in the drones is a lengthy process because at least 600 unmanned vehicles are in use along with thousands of ground stations.
Official said that systems in principal threat areas were upgraded first.
Air Force Lt. Gen. David Deptula, deputy chief of staff for intelligence, surveillance and reconnaissance, said this week that hacking is always a worry.
"Any time you have a system that is operated through command links, and that broadcasts information using omnidirectional signals, those are subject to listening and exploitation," said Deptula. "One of the ways we deal with that is encrypting signals."
Dale Meyerrose, former chief information officer for the US intelligence community, compared the problem to street criminals listening to police scanners.
"This was just one of the signals, a broadcast signal, and there was no hacking; it is the interception of a broadcast signal," said Meyerrose, who worked to field the unmanned systems in the 1990s, when he was a senior Air Force officer.
The problem, he said, is that when the drones were first being developed they were using commercial equipment, which as time goes on could become vulnerable to intercepts.
The Predator, also crucial to the war in Afghanistan and the hunt for al-Qaida and other militants in neighbouring Pakistan, can fly for hours remotely controlled by pilots thousands of miles away.
It can fly armed or unarmed and is part of a growing arsenal of such craft that includes the Reaper and Raven as well as a new, high-tech video sensor system called the Gorgon Stare, being installed on Reapers.
The military has known about the vulnerability for more than a decade, but assumed adversaries would not be able to exploit it.
Then in December 2008, the military apprehended a Shiite militant in Iraq whose laptop contained files of intercepted drone video feeds, the Journal reported.
In July, they found pirated feeds on other militant laptops, leading some officials to conclude that groups trained and funded by Iran were regularly intercepting feeds and sharing them with multiple extremist groups.
defence Secretary Robert Gates asked the Pentagon's intelligence chief, James R. Clapper Jr., to look into the problem and coordinate the work to deal with it. Officials said that when the intercepts were discovered in July 2008, it raised worries, but technical adjustments were not difficult and were put in motion quickly.
The hacking is just another example of how formidable and inventive the extremists can be. The United States has spent billions of dollars, for instance, fighting homemade bombs in Iraq and Afghanistan, the No. 1 killer of troops and weapon of choice by militants who have easy access to the materials needed to make them and use modern telecommunications networks to exchange information about how to improve them.
Pentagon spokesman Bryan Whitman said the military continually evaluates the technologies it uses and quickly corrects any vulnerabilities found.
Whitman said there were no plans to pull back on the military's use of technologies like drones, because they provide invaluable benefits to commanders.
"There's potential vulnerabilities in all of our systems," he said.