In order to attack a CTAP token, I can tap it against an ordinary phone or a Proxmark or any PN532 device attached to a computer with some fairly straightforwar

In order to attack a CTAP token, I can tap it against an ordinary phone or a Proxmark or any PN532 device attached to a computer with some fairly straightforward software. There isn’t any authentication! It could be ECDH or SnakeOil-102400-super unbreakable for all an attacker cares: the attacker can just speak the protocol as specified. edit: Okay, I found the pinToken mechanism in the spec. It is, to put it politely, not a PAKE. It has a trivial DoS attack by design allowing anyone nearby to destroy an authenticator. It looks vulnerable to an attack in which someone taps a malicious token against a phone or other reader, triggering the phone to try to authenticate, and thus captures the PIN, hashed but not even salted. Oh, and I’ve personally never been prompted to set a PIN, and the UX looks miserable.