Appointment Booking Plugin <= 5.7.4 - Unauthenticated Sensitive Information Disclosure via ORM Operator Injection in 'customer[uuid]' Parameter

The Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 5.7.4 via the 'params (customer[uuid])' parameter. This makes it possible for unauthenticated attackers to extract the first name, last name, email address, phone number, and notes of every customer record in the database by enumerating uuid prefixes via the unauthenticated steps__load_step AJAX endpoint. This vulnerability is only exploitable when the LatePoint plugin is configured with the 'Field used for authentication' setting set to 'Disable ability to login' (guest checkout mode).