Did you think hallucinations only occur in living beings whose brain signals are being tricked? Apparently not. They can occur in machines, too, sometimes with harmful results, according to Michigan State University researchers.

The team uncovered a vulnerability that could allow hackers to take over control of a drone, the quadcopters that have grown in popularity in recent years for both commercial and personal use. Left unchecked, the issue could cause big problems for companies increasingly using drones for lower emissions ways of carrying out common tasks, such as for package delivery. But the MSU team’s work is sounding the alarm for drone operators and leading to solutions.

Seeing isn’t believing

The researchers discovered a weakness in drone cameras that essentially causes the device to hallucinate, giving hackers an opportunity to manipulate the drone.

Qiben Yan, an MSU assistant professor, and his team acted like hackers during their research to replicate the problem and work toward a solution. 

“We’re kind of ‘white hat’ hackers. We attack products so their manufacturers can fix problems and protect consumers before somebody malicious takes advantage,” Yan said in a news release.

They used two bright spots of light — from flashlights or projectors, for example — to trick drones into thinking they were heading toward an obstacle. The drones “hallucinate” when the lights shine into their cameras in certain ways, and the internal software interprets this as a single obstacle in front of it. That’s when the autonomous controls kick in to make the drone avoid the obstacle, overtaking the drone pilot’s control.

The team used different light intensities and angles to change where the “obstacle” appeared. This let them control where the drone moved as it tried to avoid the obstacle. Without better security measures in place, hackers could use the same method to overtake a drone operator’s control and commandeer the device.

What’s next

In addition to spreading the word about the vulnerability to prevent drone hacking attacks, the MSU researchers are working directly with a drone company to devise defenses.

The hacking incidents can be avoided with simple measures, such as attaching lens hoods to drone cameras to block some light. Updates to the drone’s obstacle avoidance software also can help. 

The researchers’ work helps drone operators know what to look for and the importance of seeking fixes.

“Once they know the existence of an attack, they can specifically tune their algorithms for defense,” Yan said. “We don’t think it’ll be very hard to do.”