Tesla Cars Tricked Into Autonomously Accelerating 50 MPH Using Speed Sign Altered With Small Piece of Tape

Older Tesla vehicles can be tricked into accelerating by 50 miles per hour, report researchers who used tape to change a speed limit reading from 35 to 85.

Analysis shows how a camera used in 2016's Model X and Model S cars—the MobilEye EyeQ3—could be duped by a single modified number. Researchers confused a cruise control feature using a two-inch piece of black electrical tape, MIT Technology Review reported.

The analysis of the suspected vulnerability, which spanned 18 months, was run by McAfee researchers Shivangee Trivedi and Steve Povolny.

A video uploaded to YouTube showed how tape could influence Traffic-Aware Cruise Control (TACC), which used street signs to help set the car's speed.

The same feature does not appear to be implemented into new Tesla models, the team said.

"By making a tiny sticker-based modification to our speed limit sign, we were able to cause a targeted misclassification of the MobilEye camera on a Tesla and use it to cause the vehicle to autonomously speed up to 85 mph when reading a 35-mph sign," researchers said.

"For safety reasons, the video... shows the speed start to spike and TACC accelerate on its way to 85, but given our test conditions, we apply the brakes well before it reaches target speed."

"It is worth noting that this is seemingly only possible on the first implementation of TACC when the driver double taps the lever, engaging TACC," the research team conceded.

Tesla has been contacted for comment. Mobileye, an Intel subsidiary, told MIT Tech Review the team's findings were not considered to be a camera flaw as the stickers would also dupe a human driver.

"Autonomous vehicle technology will not rely on sensing alone, but will also be supported by various other technologies and data," a spokesperson said.

According to McAfee, the study's findings were disclosed to Tesla and Mobileye last year. "Both vendors indicated interest and were grateful for the research but have not expressed any current plans to address the issue on the existing platform," the blog post explained.

The EyeQ3 provides image analysis for the driver-assisted autopilot in older Model S and Model X ranges, helping the vehicles to stay in the right traffic lanes. Tesla split with Mobileye back in 2016 amid rising safety concerns surrounding self-driving car technology.

As a result, newer Tesla cars do not use MobilEye technology and researchers note they "do not currently appear to support traffic sign recognition at all."

Online, Tesla stresses its autopilot tech is an "advanced driver assistance system" and should not be used as a self-driving system. It is intended for use by a "fully attentive driver who has their hands on the wheel and is prepared to take over at any time," the firm notes.

"It does not turn a Tesla into an autonomous vehicle, and it does not allow the driver to abdicate responsibility," the electric car company says in a FAQ published to its website.

McAfee researchers found newer Mobileye cameras are not vulnerable to the sticker attack, but noted "the vulnerable version of the camera continues to account for a sizeable installation base among Tesla vehicles." Mobileye has also been contacted for comment.

"We are not trying to spread fear and say that if you drive this car, it will accelerate into through a barrier, or to sensationalize it. The reason we are doing this research is we're really trying to raise awareness... of the types of flaws that are possible," Povolny told MIT Tech Review.

The McAfee team echoed that stance while detailing the new tape research.

"Is there a feasible scenario where an adversary could leverage this type of an attack to cause harm? Yes, but in reality, this work is highly academic at this time," researchers wrote. The study took place as part of their ongoing research into adversarial machine learning.

Research published last year showed how a Tesla Model S car could potentially be coerced into switching lanes by using stickers to influence the vehicle's computer vision systems, adding to separate tests in 2018 demonstrating how the same model's key fobs could be hacked.

Last month, Tesla rejected claims made in a petition filed to the National Highway Traffic Safety Administration (NHTSA) saying its cars were accelerating without warning.

The company said the person who made the claims was a short-seller of Tesla shares, Reuters reported. The appeal suggested around 500,000 cars should be recalled.

Tesla said: "We investigate every single incident where the driver alleges to us that their vehicle accelerated contrary to their input, and in every case where we had the vehicle's data, we confirmed that the car operated as designed. In other words, the car accelerates if, and only if, the driver told it to do so, and it slows or stops when the driver applies the brake."

The following chart, which has been provided by Statista, shows the steady annual increase in the number of vehicles with autonomous driving capabilities across the world.

Statista - Autonomous driving
Statista