Ever since Apple did it, everyone jumped on the "Face Unlock" bandwagon. Except, unlike Apple, most just rely on the selfie camera and no additional hardware for a proper biometric authentication. And that just doesn't offer the same level of security. @rik demonstrated that a OnePlus 6 will happily unlock with just a photograph of a face. Even a black & white photo worked! The phone was trained on Rik's face. I printed my face to unlock my OnePlus 6 for the lulz... it worked ¯\_(ツ)_/¯ pic.twitter.com/rAVMq8JKBr rik (@rikvduijn) May 29, 2018 Well, there's a reason that...
Source: https://www.gsmarena.com/oneplus_6s_face_unlock_gets_fooled_by_a_photo-news-31370.php