What Is Car Key Hacking And How Can You Prevent It?

Published on: 15 April 2026

A new car, or even a secondhand vehicle, is a big investment. The last thing you want is to find it has been stolen. 

Over the past three decades, vehicle-related thefts have dropped. However, with more cars on the road, approximately 130,000 vehicles are still stolen each year in the UK, according to the Office of National Statistics.

This comes despite car security improving significantly with new technologies making it much harder to replicate keys and unlock vehicles. In most cases, only a qualified car locksmith and dealerships can provide replacement keys

 However, at the same time, car thieves have also gotten smarter with technology and have new ways to hack modern car keys. 

What kind of car keys can be hacked?

Keyless cars are the main target of car key hacking. These are known as keyless cars as they don’t need to be inserted and turned for unlocking and ignition. 

Car key fobs that operate via a proximity system send a signal from the fob to the car, telling it to unlock when it is nearby. 

Criminals have found a way to scan for those signals and replicate them, allowing them to access and start cars. The process is also referred to as relay theft as they use a booster to transmit the signal from your home, purse or pocket, to unlock the car. 

What stops car keys from being hacked?

There are two main ways to prevent your car key fob from being hacked. 

The first is alternative physical measures, such as using a steel steering lock, but these can be cumbersome and time-consuming. 

The second is to block the signal from your key fob. A special type of wallet called a Faraday bag uses a metal mesh to block the signal. 

Faraday bags are small enough to fit in a pocket and relatively cheap to purchase. It might just be a good investment when keeping your car and its contents safe from thieves.