Keyless entry systems offer convenience, but they also introduce vulnerabilities to modern vehicles. You might think your car is secure after locking it with your key fob, but a growing threat known as Key Fob Signal Repeaters can compromise this security, potentially leaving your vehicle vulnerable to theft.
Recently, my spouse’s car, a 2016 Subaru Outback, was rummaged through, despite her certainty that she had locked it. We live in Long Beach, California, and unfortunately, we’ve heard similar stories from neighbors and online forums. Reports of car break-ins, even without visible signs of forced entry, are becoming increasingly common. This led me to investigate the potential weaknesses of keyless entry systems, and what I discovered was eye-opening: the risk of key fob signal boosting, often executed with a key fob signal repeater.
These devices, also known as relay attack tools, exploit the technology behind keyless entry. Your key fob constantly emits a short-range radio signal. When you press a button, or simply approach your car with the fob in proximity (for passive entry systems), the car detects this signal and unlocks. A key fob signal repeater works by amplifying and relaying this signal. Thieves using this device can stand near your house, capture the signal from your key fob (even if it’s inside), amplify it, and transmit it to your car as if you were right next to it with your key. This fools your car into unlocking, allowing thieves to enter and potentially steal valuables or even the entire vehicle.
Initial online searches about keyless entry vulnerabilities might seem alarming, sometimes even venturing into “foil-hat” territory. However, searching for “keyless entry hack” or, more specifically, “key fob signal repeater,” reveals credible information about this real threat. Reputable publications like Wired Magazine and The New York Times have reported on these vulnerabilities and the devices used to exploit them. These articles confirm that this isn’t just a theoretical risk; it’s a practical method used by thieves to bypass car security systems.
So, what can you do to protect yourself from key fob signal repeater attacks? One effective and surprisingly simple solution is to use a Faraday cage. A Faraday cage is an enclosure that blocks electromagnetic fields, including the radio signals emitted by your key fob. By storing your key fob inside a Faraday cage when you’re at home, or anywhere your car is parked and vulnerable, you effectively shield its signal, preventing a key fob signal repeater from capturing and relaying it.
You don’t need to buy expensive, specialized Faraday enclosures. In fact, a common household item can work remarkably well: a cocktail shaker. My decision to use a cocktail shaker as a Faraday cage was driven by practicality and cost-effectiveness. Coming home and dropping my keys into a shaker is much easier than dealing with small Faraday pouches every time, although those pouches are also a viable option. Cocktail shakers are also generally less expensive than commercially marketed Faraday pouches or boxes designed for key fobs.
To ensure its effectiveness, I tested the cocktail shaker as a Faraday cage, and it worked perfectly. We even tried some tin boxes we had around the house, but they unfortunately failed to block the signal. If you’re interested in seeing this in action, a quick search on YouTube for “cocktail shaker Faraday” will yield demonstrations and further information.
Protecting your vehicle from key fob signal repeater attacks doesn’t have to be complicated or costly. By understanding the threat and taking simple preventative measures like using a DIY Faraday cage, you can significantly reduce your risk of becoming a victim of this modern car theft technique. Consider a cocktail shaker, a metal box, or a Faraday pouch as a simple and effective shield against key fob signal theft and enjoy greater peace of mind knowing your car is more secure.
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