Smart Lock Security: Are Connected Locks Safe?

Smart locks have become increasingly popular, offering the ability to lock and unlock your door with a smartphone, grant temporary access to guests, and receive notifications when someone enters your home. But entrusting your home physical security to a connected device raises important questions. Are smart locks actually secure, and what precautions should you take if you decide to use one?

How Smart Locks Work

Smart locks replace or augment traditional deadbolts with electronic locking mechanisms controlled through wireless communication. Most smart locks connect via Bluetooth, WiFi, Z-Wave, or Zigbee. They can be controlled through a companion app on your smartphone, voice assistants like Alexa or Google Home, keypads with PIN codes, or traditional physical keys as a backup.

The lock communicates with a hub or directly with your home WiFi network to enable remote access, automation, and integration with other smart home devices. Premium models include features like auto-lock, geofencing (automatic unlock when you approach), and detailed access logs.

Security Vulnerabilities

Like any connected device, smart locks have potential vulnerabilities. Bluetooth-based attacks can target locks that use older Bluetooth protocols with known weaknesses. Researchers have demonstrated attacks that can intercept the Bluetooth communication and replay it to unlock the door.

WiFi-connected locks are subject to the same network vulnerabilities as any other IoT device. If your WiFi network is compromised, an attacker could potentially control your smart lock. This is why securing your home network is a prerequisite for using any smart home security device.

Some smart locks have been found to have firmware vulnerabilities that allow attackers to bypass authentication. While reputable manufacturers quickly patch such issues, cheaper locks from unknown brands may never receive security updates.

Physical attacks remain a concern as well. Some smart locks have been found to be easier to physically manipulate than quality traditional deadbolts. The electronic components can add complexity that creates physical weak points.

Choosing a Secure Smart Lock

Select a smart lock from a reputable manufacturer with a track record of security updates and prompt vulnerability responses. Look for locks that use AES-128 or AES-256 encryption for communication. The lock should support two-factor authentication for remote access and should use encrypted, randomized codes rather than static ones.

Choose a lock that retains a traditional key backup. This ensures you can always access your home even if the electronics fail, the battery dies, or the associated cloud service goes down. A smart lock without a physical key backup creates a potential lockout risk.

Check whether the manufacturer provides regular firmware updates and how long they have committed to supporting the product. A smart lock that stops receiving updates becomes increasingly vulnerable over time.

Installation Best Practices

When installing a smart lock, start by making sure your door and frame are in good condition. The best smart lock cannot compensate for a flimsy door or poorly aligned strike plate. Consider upgrading your strike plate to a reinforced model with longer screws that anchor into the door frame studs.

During setup, use a strong, unique password for the smart lock account. Enable two-factor authentication. Do not reuse the PIN code from other devices or accounts. Set the PIN to at least six digits and avoid obvious patterns like 123456 or your birthday.

Network Security for Smart Locks

Place your smart lock on a separate network segment from your computers and phones. If an IoT device on your network is compromised, network segmentation prevents the attacker from reaching your smart lock through the compromised device.

Use WPA3 encryption on the network your smart lock connects to. Keep your router firmware updated. If your smart lock uses a hub, keep the hub firmware updated as well.

Disable any smart lock features you do not use. If you do not need voice assistant integration, disable it. If you do not need remote access, disable it. Each enabled feature is a potential attack surface.

Managing Access

Review and update access permissions regularly. Remove temporary access codes after they are no longer needed. If you grant access to a house cleaner, dog walker, or contractor, create time-limited codes that automatically expire.

Monitor the access log for any unexpected entries. Most smart lock apps provide a detailed log showing who unlocked the door and when. Investigate any entries you do not recognize.

When moving into a new home with an existing smart lock, perform a factory reset and set up the lock as new. The previous owner may still have access through an old account or saved codes.

The Verdict

Smart locks are generally safe when properly selected, installed, and maintained. They offer genuine security benefits like access logging, temporary codes, and automatic locking that traditional locks cannot provide. However, they require ongoing attention to firmware updates, account security, and network protection. For most homeowners, the convenience and additional features of a well-chosen smart lock outweigh the risks, provided you follow security best practices.

Conclusion

Smart locks can be a secure addition to your home when you choose a reputable brand, maintain strong network security, and follow best practices for configuration and access management. Treat your smart lock with the same security diligence you apply to other critical connected devices, and it will serve you well.