The OKLOK (3.1.1) mobile companion app for Fingerprint Bluetooth Padlock FB50 (2.3) allows remote attackers to submit API requests using authenticated but unauthorized tokens, resulting in IDOR issues. A remote attacker can use their own token to make unauthorized API requests on behalf of arbitrary user IDs. Valid and current user IDs are trivial to guess because of the user ID assignment convention used by the app. A remote attacker could harvest email addresses, unsalted MD5 password hashes, owner-assigned lock names, and owner-assigned fingerprint names for any range of arbitrary user IDs.