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.

Operating in pairs, one criminal holds a device up against the car door, amplifying the signal it broadcasts around the perimeter of the vehicle. Another stands near the front wall or porch of a home, with a device that relays the key’s signal back to his accomplice.

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 a second time, starting the engine. 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 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. Many carmakers have now introduced motion-sensor enabled fobs, which go to sleep when idle and can’t fall victim to the Relay Attack. If a fob of this type is not available, find out if your current fob can be switched off overnight
  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. This is very easy to do – simply pop your fob into the pouch, walk up to your car and see if the door will open

Find out more about the vulnerability here