Appointment Booking Calendar — Simply Schedule Appointments: A security weakness
Appointment Booking Calendar — Simply Schedule Appointments is affected by a security weakness. The vulnerable path is reachable without authentication. The resulting impact depends on how the affected component exposes the vulnerable operation.
- Component
- Appointment Booking Calendar — Simply Schedule Appointments
- Plugin slug
simply-schedule-appointments- Affected
- See vendor advisory
- Safe version
- See mitigation notes
- Published
- Mar 13, 2026
- Weakness
- CWE-862 — Missing Authorization
This CVE was published Mar 13, 2026 and is one of 31 known issues for this plugin.
Update, patch or deactivate.
Update Appointment Booking Calendar — Simply Schedule Appointments to a release outside the affected range, or disable and remove it until a fixed version is available.
No confirmed safe version is listed. Consider a vendor-supported patch or temporarily restricting the affected functionality while you assess the risk.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
The Appointment Booking Calendar — Simply Schedule Appointments plugin for WordPress is vulnerable to unauthorized access of sensitive data in all versions up to and including 1.6.9.29. This is due to two compounding weaknesses: (1) a non-user-bound `public_nonce` is exposed to unauthenticated users through the public `/wp-json/ssa/v1/embed-inner` REST endpoint, and (2) the `get_item()` method in `SSA_Settings_Api` relies on `nonce_permissions_check()` for authorization (which accepts the public nonce) but does not call `remove_unauthorized_settings_for_current_user()` to filter restricted fields. This makes it possible for unauthenticated attackers to access admin-only plugin settings including the administrator email, phone number, internal access tokens, notification configurations, and developer settings via the `/wp-json/ssa/v1/settings/{section}` endpoint. The exposure of appointment tokens also allows an attacker to modify or cancel appointments.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N