QR code pairing is a setup method where one device displays a scannable code and another device reads it to exchange connection details. It is common in phones, consoles, smart home gear, and accessories because it avoids manual typing and can speed up onboarding. The QR code usually carries a token, network information, or a handshake value that helps both sides establish trust.
In security terms, QR code pairing is an input path and a trust boundary. If the code is visible to a nearby attacker, they may be able to start an unwanted pairing attempt, capture a session token, or feed malformed data into the parser that handles the code. Defenders should treat QR payloads like any other untrusted input: validate them, limit what they can authorize, time-limit pairing windows, and require an extra confirmation step before sensitive actions. When implemented well, QR pairing is convenient; when implemented poorly, it can become a local attack surface.