This following issue has been reported by Bkis: Vulnerability in Face Recognition Authentication Mechanism of Lenovo-Asus-Toshiba Laptops.
Modern laptops have often a small built in camera on top of the screen. Some vendors developed software’s to perform face recognition authentication. Theoretically, the principle is very attractive: the computer recognizes the visage of the user who sits in front of its keyboard and allow or denies access to the system.
Once again, the main issue of the lack of authentication factors. Remember: something you know, something you have or something you are. A strong authentication is performed by the combination of minimum two of those factors.
Bkis also provided a demo of this vulnerability.