The Appointment Booking Calendar Plugin and Online Scheduling Plugin – BookingPress plugin for WordPress is vulnerable to authentication bypass in versions 1.1.6 to 1.1.7. This is due to the plugin not properly verifying a user's identity prior to logging them in when completing a booking. This makes it possible for unauthenticated attackers to log in as registered users, including administrators, if they have access to that user's email. This is only exploitable when the 'Auto login user after successful booking' setting is enabled.

The BookingPress Pro plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the 'bookingpressvalidatesubmittedbookingformfunc' function in all versions up to, and including, 5.6. This makes it possible for unauthenticated attackers to upload arbitrary files on the affected site's server which may make remote code execution possible. Note: The vulnerability can only be exploited if a signature custom field is added to the booking form.

The Appointment Booking Calendar Plugin and Scheduling Plugin WordPress plugin through 1.1.28 does not validate data before passing it to a PHP deserialization function, allowing unauthenticated attackers to inject arbitrary PHP objects; where a suitable gadget chain is present on the site this can be leveraged to achieve remote code execution.

The Appointment Booking Calendar Plugin and Scheduling Plugin WordPress plugin before 1.1.23 export settings functionality exports data to a public folder, with an easily guessable file name, allowing unauthenticated attackers to access the exported files (if they exist).

The BookingPress plugin for WordPress is vulnerable to arbitrary file uploads due to insufficient filename validation in the 'bookingpressprocessupload' function in all versions up to, and including 1.0.87. This allows an authenticated attacker with administrator-level capabilities or higher to upload arbitrary files on the affected site's server, enabling remote code execution.

The Appointment Booking Calendar Plugin and Scheduling Plugin – BookingPress plugin for WordPress is vulnerable to SQL Injection via the 'category' parameter of the 'bookingpressform' shortcode in all versions up to, and including, 1.1.21 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for authenticated attackers, with Contributor-level access and above, to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database.