CVE-2026-6937 Missing authorization in Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin
Unauthenticated attackers can modify arbitrary appointment records and expose customer PII via the bulk appointments REST API endpoint due to missing authorization checks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-6937?
CVE-2026-6937 is a medium-severity missing authorization vulnerability in croixhaug Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin, published on 28 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 1.6.11.8 due to the plugin not properly verifying that a user is authorized to perform an action via the bulk appointments REST API endpoint. This makes it possible for unauthenticated attackers to modify arbitrary appointment records including customer PII, payment status, and meeting URL fields, and to expose full customer PII from existing appointment records via the bulk endpoint response. The public nonce is a static, user-independent value present in the HTML source of any page hosting the [ssa_booking] shortcode, meaning any visitor who has viewed such a page can obtain it and target any appointment in the system without authentication.
Weakness: CWE-862
Which versions are affected by CVE-2026-6937?
How do I fix CVE-2026-6937?
No fix has been published for CVE-2026-6937 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-6937 being exploited?
There is no known exploitation of CVE-2026-6937 in the wild and no public exploit code.
Sources
Also known as GHSA-4cp9-7xpg-wmvc.