The miniOrange 2FA WordPress plugin before 6.2.6 does not validate the submitted one-time password against the targeted users stored secret, instead verifying it against an attacker-supplied value, allowing an unauthenticated attacker who knows a victims password to bypass two-factor authentication and gain access to the victims account, including administrators.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.