CVE-2026-108758

Description

Easy!Appointments through 1.6.0 contains an authorization bypass vulnerability in Booking::register() that allows unauthenticated attackers to modify any appointment by supplying an appointment id without its hash. Attackers can enumerate sequential appointment ids with a self-asserted manage_mode flag to rewrite appointment details, rebind them to attacker-controlled customers, and obtain management hashes for rescheduling or cancellation.

References

• https://github.com/alextselegidis/easyappointments
• https://github.com/alextselegidis/easyappointments/blob/4bc7ecd51f3dade8e041558f2c23dda65bd6c43e/application/controllers/Booking.php#L368-L587
• https://github.com/alextselegidis/easyappointments/commit/09c6fb30b6aac0830a820d6bec3d2eb241daf150
• https://hackmd.io/@haind/easyappointments-booking-register-appointment-takeover
• https://www.vulncheck.com/advisories/easy-appointments-through-1.6.0-authorization-bypass-via-booking-register-endpoint