Apple is naturally no stranger to controversy, especially when it comes to iPhones and its biometric security systems. There were some raised questions and eyebrows when it first introduced Touch ID and there are even more now after it launched Face ID on the iPhone X. It was almost as if Apple were daring people to prove the 3D face recognition technology to be as fallible as some critics suggest. While indubitable proof has yet to be presented, two brothers may have come across a way to train Face ID to accept someone else’ face. Provided that someone else looks like you.
Face ID is, fortunately, not the only way into the iPhone. Like Touch ID, it still falls back on the 6-digit PIN code when attempts fail. Unlike Touch ID, however, Face ID uses machine learning and artificial intelligence to improve its face recognition. And that could be used against it, if this theory turns out to be correct.
According to that theory, entering the correct PIN code after a failed face recognition attempt basically tells Face ID that the “failed” face is actually correct. After several such attempts, Face ID will eventually learn to recognize the other face as you and will unlock the phone for both faces.
Of course, this won’t happen with just any other face. The only reason it really worked for the brothers is that they look very much alike. There are already reports of Face ID failing to distinguish between twins or look-alikes.
The other caveat is that, in order to train Face ID to recognize someone else, that someone else has to know your PIN code. And when someone else knows your PIN code, sibling or not, neither Face ID nor even Touch ID will be able to stop them from getting into your iPhone anyway.