Brief Explanation of Modern Car Theft

New technology in the car-making industry has brought a change in the methods criminals use to steal vehicles — they now do it with electronic devices that can sometimes be built for as little as $11. The approach may seem perplexing, but the explanation is simple.

Older cars use a mechanical system to lock the doors, one that can be bypassed using the most unexpected tools: from a tennis ball or a wire coat hanger to a shoestring. But modern vehicles rely on power locks controlled by radio frequency communication between the key and the automobile, up to a certain distance.

Reports of car thieves making off with expensive, keyless vehicles have increased lately in the mainstream media, with accounts of criminals approaching the target with a mysterious device and unlocking the doors in seconds. Other times they did not even display a gadget at all and simply entered the vehicle. In these examples, the attacker intercepted the radio signal (relay and replay attacks) and used it to get into the car or block it altogether.

A popular attack is relay, which involves two transceivers that create a bridge between the key and the car, tricking the receiver into believing the transmitter is nearby. The result is an unlocked door and starting the engine for the keyless systems. Research on this method exists since 2011, and the difference since then are the costs for building the attack device and significant range improvements.

A replay charge consists of recording the commands from the key fob and feeding them to the receiver later. This method is more difficult because it requires cracking the codes before replaying them to the target. When it was presented in 2015 by Samy Kamkar, building the device cost $32. More refined the cost of such software defined radio (SDR) hardware reaches a few hundred US dollars.

A third technique to break into a car is the simplest of all, and it involves jamming the signal from the key fob to the car, preventing the commands from being sent. An owner who does not notice the signs the car gives when it locks down would actually leave it open to robbery. These gadgets can be purchased online and the cheaper ones can cover a 50m area.

Auto theft reports have increased in recent years as criminals have brushed up their tech skills and learned to build the signal manipulating gadgets. In the case of amplification attacks, one solution to prevent them is to protect the key fob from emitting the radio wave. If it cannot be turned off, it can be disabled by placing it in a tin box or wrapping it in tin foil, to obtain a result similar to a Faraday cage; even if the signal is not blocked completely, it would definitely become weaker.