Foil-wrapped car keys: A simple shield against relay theft

The "relay attack" method has become common in many countries, such as the United Kingdom. Edmund King, the leader of the British Automobile Association, recently urged drivers in the "Daily Mail" to be more cautious and better secure their car keys.

His wife fell victim to this method when her Lexus, worth approximately £55,000, was stolen. How does it work? Thieves target cars with keyless entry systems. One thief approaches the door of a residence with a device that activates the key fob signal, which is then transmitted further.

The second thief near the vehicle uses a device resembling a suitcase, which receives the signal and relays it to the car. The car recognises the signal as if the key fob were right next to the doors, allowing it to be opened and the engine to be started without the physical presence of the key fob.

Once the car is started, the key fob doesn't need to be in the vehicle—it will drive until the engine is turned off. Thieves just have to deal with warning sounds and messages on the dashboard.

Research conducted by King shows that 51% of car owners with keyless entry do not use additional security measures. After the unfortunate incident, King keeps his keys in a signal-blocking case, which he places in a metal box, and that, in turn, goes into the microwave.

While such measures may seem excessive, it's worth taking certain security steps. You can buy special cases for keys online, which can be stored in a metal container or pot. The most important thing is that the keys are not left near the doors. Edmund also recommends wrapping the key fob in aluminium foil. This is a cheap and simple way to protect your car from thieves. A few months ago, we tested how effective this method is, and the results can be found below.