The Booking Calendar and Notification plugin for WordPress is vulnerable to unauthorized access, modification, and loss of data due to missing capability checks on the wpcb_all_bookings(), wpcb_update_booking_post(), and wpcb_delete_posts() functions in all versions up to, and including, 4.0.3. This makes it possible for unauthenticated attackers to extract data, create or update bookings, or delete arbitrary posts.
The product does not perform an authorization check when an actor attempts to access a resource or perform an action.