The Hydra Booking — Appointment Scheduling & Booking Calendar WordPress plugin before 1.2.2 does not verify that a booking belongs to the requesting user before modifying or deleting it on two of its booking endpoints, allowing a booking-provider-level user to cancel and permanently delete other providers' bookings on the same site.
https://wpscan.com/vulnerability/3685e160-f3a4-4772-b2e3-f6155894ab4c/