Speaking on a panel on national security, Wray said the FBI views self driving cars as a possible tool that terrorists could use to cause physical harm and a potentially valuable source of personal data to exploit.

“When you talk about autonomous vehicles, it’s obviously something that we’re excited about, just like everybody,” the FBI director said. “But there are harms that we have to guard against that are more than just the obvious.”

“One of them is the danger that there could be ways to confuse or distort the algorithms to cause physical harm.”

“I’m thinking about a story I heard not that long ago about the researchers who were able to trick a self-driving car’s algorithm by essentially putting a piece of black tape over a stop sign. It caused the car to accelerate about 50 miles an hour or something.”

“It’s a simple example, but it shows some of the harms we have to guard against,” Director Wray said.

“A different kind of harm we’re concerned about is the enormous amount of data that autonomous vehicles, for example, aggregate. And any time you aggregate lots and lots of sensitive data, it makes a very tempting target,” and are“very much on our mind” in the federal government. Wray added.

He said the expanding use of self-driving cars is an example of a new “attack surface” that terrorists will try to use to their advantage.

The Insurance Institute for Highway Safety expects there to be 3.5 million self-driving cars on U.S. roads by 2025.