How safe is a keyless entry car?
Keyless-entry cars are convenient but carry security risks. In practice, attackers can exploit radio signals to unlock and start a vehicle even when the owner isn’t nearby. Taking precautions and keeping vehicle software current can significantly reduce that risk.
How keyless entry works
Keyless-entry systems use a fob that communicates with the car when it is within a certain distance. When the car detects the fob, it unlocks the doors and may allow starting the engine if the fob is inside the vehicle. Modern systems typically rely on encrypted, rolling codes and immobilizers to prevent reuse of captured signals, but gaps remain in some implementations and in older designs.
What makes them vulnerable
There are several vulnerabilities that have been demonstrated or reported by researchers and in theft cases. The following points describe the most common weaknesses:
- Relay attacks that capture a fob’s signal near the owner (for example, inside a home) and relay it to the car, effectively extending the fob’s range.
- The use of two devices in a relay setup: one near the house and one near the car, allowing entry and ignition even when the fob is inside the owner’s residence.
- Older or poorly implemented systems where signals can be intercepted and replayed due to weak encryption or insufficient rolling-code protection.
- Compromised mobile apps or connected services that can indirectly affect access or starting ability if the vehicle’s connected features are breached.
- Physical exposure or tampering that targets weaker IMMO (immobilizer) implementations or poorly protected entry points, especially in vehicles with less robust anti-theft measures.
Car makers have responded with stronger encryption, more robust immobilizers, and updates delivered over-the-air to address these vulnerabilities. Even so, the combination of proximity-based entry and remote access features means the risk is not zero and varies by model and region.
How theft plays out in the real world
In many places, thieves have used relay devices to steal cars parked near residences, often with little disruption to the neighborhood. The risk is higher for vehicles that rely heavily on passive entry and for owners who keep fobs near doors or windows. While high-end models may have stronger protection, no system is foolproof, and regional crime trends influence risk levels.
How to improve safety
There are practical steps owners can take to reduce the chances of a keyless-entry theft. The list below outlines common, effective measures:
- Store keys in a Faraday pouch or a metal-lined container to block signal transmission when not in use.
- Keep keys and fobs away from exterior doors and windows; avoid leaving them in easy-reach spots near entrances.
- Disable passive entry or auto-unlock features if you don’t rely on them, or switch to manual locking when you’re away from the car for extended periods.
- Regularly install manufacturer-provided software updates and security patches for the vehicle’s infotainment and security systems.
- Enable additional authentication where available, such as a PIN-to-drive or driver authentication feature offered by some models.
- Use a physical anti-theft device (e.g., steering-wheel lock) and consider a discreet vehicle tracker as part of your insurance or security plan.
- Park in a secure garage when possible or in well-lit, monitored areas, especially overnight in urban environments.
- Limit the use of connected remote features when not needed, and ensure your smartphone and car apps are protected with strong passwords and two-factor authentication where offered.
While these steps cannot guarantee zero risk, they significantly raise the barrier to theft and reduce exposure to common attack methods.
Bottom line
Keyless-entry systems offer clear convenience but come with tangible security trade-offs. The most effective defense combines updated vehicle security features, responsible handling of the fob, and smart preventative measures at home and on the road. The level of safety varies by vehicle model, region, and how responsibly the owner applies protective practices.
Summary
- Keyless-entry is convenient but can be vulnerable to relay and related attacks that bypass proximity safeguards.
- Security improves with encryption, OTA updates, and features like PIN-to-drive in some models.
- Owners can reduce risk by storing fobs in Faraday pouches, disabling passive entry when not needed, updating software, and using additional physical or tracking deterrents.
