https://wccftech.com/future-airpods-might-authenticate-your-identity-through-the-shape-of-your-ear-canal/

Apple was previously rumored to include in-display Touch ID on future iPhone models along with Face ID. However, Apple could potentially move away from both options and devise an all-new method of authentication. A recently filed Apple patent hints at using AirPods for authentication. Scroll down to read more details on the subject.

The new Apple patent is titled "User Identification Using Headphones" and filed with the USPTO (via Patently Apple). The patent explains how the system can make use of AirPods to authenticate users using nearby devices, ultrasonic signals, voice recognition, and more. The patent also describes a potential security risk with wireless headphones as anyone can wear them to access information.