The Salon Booking System WordPress plugin through 10.31.0 does not verify that a requested booking belongs to the caller on one of its REST API endpoints, requiring only a basic read capability, allowing any authenticated user (including a Subscriber or self-registered customer account) to disclose any customer's booking personal data such as name, email, phone number, address and private notes by enumerating booking identifiers.
https://wpscan.com/vulnerability/6e7852e9-0acd-4a79-9240-b864b14459a3/