CVE-2026-4807
CVE-2026-4807: medium vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.
- CVSS
- 6.5 MEDIUM
- EPSS
- 39.44%
- Known exploited
- not in KEV
- Product
- -
What is known
The Appointment Booking Calendar plugin for WordPress is vulnerable to Missing Authorization in versions up to and including 1.6.10.6. This is due to a flawed authorization logic in the nonce_permissions_check() method combined with the public exposure of a site-wide reusable nonce. The plugin exposes a public_nonce value through the /wp-json/ssa/v1/embed-inner endpoint, which is accessible to unauthenticated users. The appointment deletion endpoint at /wp-json/ssa/v1/appointments/{id}/delete and /wp-json/ssa/v1/appointments/bulk use a permission check that accepts requests containing both an X-WP-Nonce header (with any arbitrary value) and an X-PUBLIC-Nonce header (with the valid public nonce). When the X-WP-Nonce validation fails, the function falls back to validating the X-PUBLIC-Nonce without properly rejecting the request. Since the public_nonce is exposed to all unauthenticated visitors and is site-wide (not user-specific or appointment-specific), attackers can obtain it and use it to view details of arbitrary appointments, including the public_edit_url, or delete arbitrary appointments by ID. This makes it possible for unauthenticated attackers to view, delete or modify any appointment in the system, disclosing sensitive appointment data, causing service disruption, and loss of booking records.
Business impact
Successful exploitation of CVE-2026-4807, a medium vulnerability (CVSS 6.5) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.
Recommended administrator action
Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.