Keyless car smart keys susceptible to relay attacks; Faraday‑style protectors advised

Modern keyless entry systems transmit a radio signal from the smart key to the vehicle, allowing thieves to capture or relay the code and unlock or start the car without physical force. Common methods include relay attacks that bounce the signal between two devices, OBD‑based cloning that creates a new key in seconds, and direct radio interception of contactless credit‑card‑type signals.

Experts recommend shielding the key in a Faraday‑cage container—such as a purpose‑built card protector or a simple wrap of aluminum foil—to block radio waves. The foil or conductive enclosure creates a miniature Faraday cage that prevents the key’s signal from being read, reducing the risk of relay‑theft. Additional measures include storing the key away from doors, using aftermarket anti‑theft systems, and keeping the vehicle’s software updated.