CVE-2026-52839

Easy!Appointments is a self hosted appointment scheduler. Versions prior to 1.6.0 correctly filter provider-scoped appointments in the `appointments/search` response, proving that provider isolation is an intended security boundary. However, the direct mutation endpoints `appointments/store` and `appointments/update` only check generic appointment privileges and never verify that the submitted `id_users_provider` belongs to the current session. A normal authenticated provider can inject new appointments into another provider's schedule via `store`, or reassign existing appointments into a foreign provider's calendar via `update`. The `store` path contains an additional write-before-crash bug: the unauthorized row is committed to the database before the controller crashes on a type error, so the attacker receives an error response while the foreign appointment is already persisted. Version 1.6.0 patches the issue.

• github.comhttps://github.com/alextselegidis/easyappointments/commit/4abb10545d83ac1a57d03f6502376ee67696ea7c
• github.comhttps://github.com/alextselegidis/easyappointments/security/advisories/GHSA-w8xc-8g92-v77h
• github.comhttps://github.com/alextselegidis/easyappointments/security/advisories/GHSA-w8xc-8g92-v77h