YouTuber Mark Rober has released a video in which he used a homemade relay attack device to steal a car from popular Twitch streamer JasonTheWeen live on stream.
The video demonstrates the dangers of keyless entry car theft, showing how devices that intercept the signal between a car and its key fob inside a house can be used to unlock and start a vehicle in seconds.
Rober originally purchased a $12,000 “relay attack” device from a hesitant black market dealer named Dimitri before reverse-engineering it using parts from a 2004 video baby monitor, bringing the cost down to around $100
Rober steals JasonTheWeen’s giveaway car to prove his point
Rober selected JasonTheWeen’s giveaway, a brand new 2026 Hyundai Sonata, as the live test vehicle.
While Jason was streaming inside the former FaZe house, Rober and fellow CrunchLabs employee Ian snuck into Jason’s driveway, seen on security cameras as they approached the front door.
Using the homemade device, Rober was able to unlock, start and flee inside the giveaway vehicle only with the streamers manager calling to inform him of what had taken place.
But rather than simply return it, Rober had a bigger plan in mind. Having already fitted the Sonata with 12 GPS trackers and hidden cameras, he left it parked on a Los Angeles street with the highest auto theft rate in the city to see what would happen next.
Shortly after at 2:15 am, a teenager stole the Sonata and spent the night joyriding. After five days of tracking, GPS data showed the car had been impounded for a parking violation.
Rober later came clean to Jason and replaced the lost Sonata with a brand new 2026 Rivian for his audience giveaway, with 10 finalists competing on a live stream on June 28.
To protect against relay attacks, Rober recommends keeping key fobs away from front doors and storing them in a metal tin or wrapping them in a single layer of aluminum foil.
It is not the first time Rober has used engineering to expose real-world crime. His glitter bomb package thief trap series has caught dozens of porch pirates on camera using hidden cameras and fart spray hidden inside decoy packages.
