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.
https://plugins.trac.wordpress.org/changeset/3595856
https://plugins.trac.wordpress.org/browser/easy-appointments/tags/3.12.25/src/ajax.php#L2656
https://plugins.trac.wordpress.org/browser/easy-appointments/tags/3.12.25/src/ajax.php#L183
https://plugins.trac.wordpress.org/browser/easy-appointments/tags/3.12.25/src/ajax.php#L115
https://plugins.trac.wordpress.org/browser/easy-appointments/tags/3.12.22/src/ajax.php#L2656
https://plugins.trac.wordpress.org/browser/easy-appointments/tags/3.12.22/src/ajax.php#L183
https://plugins.trac.wordpress.org/browser/easy-appointments/tags/3.12.22/src/ajax.php#L115