Easy Appointments <= 3.12.27 - Missing Authorization to Authenticated (Contributor+) Sensitive Customer Information Exposure via ea_get_customers_ajax AJAX Action

The Easy Appointments plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 3.12.27 via the handle_customers_ajax. This makes it possible for authenticated attackers, with contributor-level access and above, to extract the full customer dataset from the ea_customers table, including personally identifiable information such as names, email addresses, mobile numbers, dates of birth, and physical addresses.