Bonding is the Bluetooth process of saving shared keys after pairing so two devices can recognize each other later without repeating the full setup. Once bonded, a phone, headset, or sensor can reconnect by proving it has the stored credentials, which makes future connections faster and more seamless.
In cyber security, bonding matters because it turns a one-time pairing decision into a lasting trust relationship. If an attacker can force pairing, steal bonding keys, or abuse a weak authentication step, they may later reconnect as a trusted peer. That can lead to device impersonation, unauthorized audio access, session hijacking, or persistent access to a wearable or accessory. Defenders reduce this risk by limiting pairing mode, removing unknown bonded devices, resetting compromised hardware, and ensuring bonding keys are erased when devices are reinitialized.