The Relay Attack: Guidance for concerned car owners

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This theft technique, covered widely by the media, exploits a potential vulnerability in so-called ‘keyless entry’ systems and is known as Relay Theft or the Relay Attack.

What is Relay Theft?

Relay theft exploits a vulnerability in passive keyless entry systems, which allow drivers to open and start their cars without removing the keyless fob from their pocket.

Usually operating in pairs, one criminal holds a device up against the front wall or porch of a home, searching for a signal from the keyless fob. The device then relays the key’s signal to an accomplice, who is holding another device against the car door.

The car is effectively fooled into believing that the owner is within a defined range (usually two metres) and is approaching the car with their key. The door opens, and the signal is relayed to the accomplice a second time, allowing the car to start. Once started the engine will not restart without the key present.

What should I do?

If you are worried that your car could be subject to this theft technique, the first question to ask is, “do I have a keyless entry system?”

Keyless entry fobs should not be confused with standard remote fobs. If you have to push a button on the fob to gain entry, it’s not a keyless system and your car is not vulnerable to relay theft.

If you do have a car with a keyless entry system, and you’re concerned, please follow our guidance to make things as tough as possible for thieves:

  1. Ask your dealer: if you’re not sure, get clarity on whether you have a keyless entry system or not. If you do, find out if your keyless fob can be switched off overnight. Speak to your dealer about software updates, and whether your carmaker is bringing in new keyless fobs with added security
  2. Don’t make it easy: store all keys – spares included – away from household entry points. Also, be vigilant and report any suspicious behaviour in your neighbourhood to the Police
  3. Make sure shielding devices work: Faraday pouches and containers can block the signal from a keyless entry fob – but it is important that you test they are effective first

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