You walk outside in the morning and your car is gone. The keys are still on the shelf, the door was not forced and there is no broken glass. The thieves did not need to touch your key. They only had to extend its signal.
This method is known as a relay attack, and it targets vehicles with keyless entry and starting systems.
How does a keyless system work?
A keyless system continually checks whether the correct key is close to the vehicle. When you approach, the car recognises its signal and allows you to unlock the doors or start the engine without pressing a button.
Thieves can exploit this convenience. They usually work in pairs. One approaches the location where the key is stored, such as a door or window, while carrying a receiver. The other waits beside the vehicle with another device. Their equipment relays the communication so that the car believes the key is directly beside it.
The vehicle unlocks and, with some models, can also be started. There is no broken window, damaged lock or physically stolen key.
Are all keyless cars at risk?
Not every vehicle is equally vulnerable. Newer models may use more precise UWB technology that can determine the key’s actual distance more reliably. Some key fobs also enter sleep mode after remaining motionless for a certain period.
The risk has not disappeared, however. In 2026, ADAC reported that approximately 30% of the 850 vehicles it tested still needed better protection against keyless theft.
What can you do?
Keep your keys, including the spare, away from entrance doors and windows. Check the vehicle manual as well, because some models allow keyless functions to be disabled.
A simple physical safeguard is a properly closed Faraday bag, which limits wireless communication with the key stored inside. The FWR Faraday bag for keyless vehicle remotes is designed specifically for keyless fobs. It has compact dimensions and measured maximum signal attenuation of up to 60 dB.
The key must be placed inside the shielded compartment and the Faraday bag must be closed carefully. You can test it easily: insert the key, close the Faraday bag and try to unlock your vehicle. The car should not respond to the protected key.
For greater protection, combine the Faraday bag with a steering-wheel lock, secure parking or a vehicle tracking system.
Convenience does not have to mean an easy target
A relay attack does not crack the key’s code or physically force the car open. It simply convinces the vehicle that the correct key is closer than it really is.
The good news is that protection does not have to be complicated. Storing both keys correctly, checking your vehicle settings and using a high-quality Faraday bag can significantly reduce the risk of a convenient keyless system becoming an entry point for thieves.
