CVE-2026-4807: CWE-862 Missing Authorization in croixhaug Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin
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.
AI Analysis
Technical Summary
CVE-2026-4807 is a missing authorization vulnerability (CWE-862) in the Appointment Booking Calendar plugin for WordPress, specifically in versions up to 1.6.10.6. The vulnerability stems from a flawed authorization check in the nonce_permissions_check() method, which improperly validates requests using a public_nonce exposed via the /wp-json/ssa/v1/embed-inner endpoint. The plugin's appointment deletion endpoints accept requests with an X-WP-Nonce header and an X-PUBLIC-Nonce header. When the X-WP-Nonce validation fails, the function falls back to validating the X-PUBLIC-Nonce without rejecting the request. Since the public_nonce is site-wide and accessible to unauthenticated users, attackers can exploit this to view or delete arbitrary appointments by ID, compromising appointment confidentiality and integrity.
Potential Impact
An unauthenticated attacker can leverage this vulnerability to view sensitive appointment information, including public_edit_url details, delete arbitrary appointments, and modify booking records. This results in unauthorized disclosure of sensitive data, loss of appointment records, and potential disruption of the appointment booking service. The CVSS score of 6.5 (medium severity) reflects the network attack vector, low attack complexity, no privileges required, no user interaction, and impact on integrity and availability but no direct confidentiality impact.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. There is no official fix or patch information available at this time. Until a patch is released, users should consider disabling the affected plugin or restricting access to the vulnerable REST API endpoints to trusted users only. Monitor vendor channels for updates and apply official patches promptly once available.
CVE-2026-4807: CWE-862 Missing Authorization in croixhaug Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin
Description
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.
CVSS v3.1
Score 6.5medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-4807 is a missing authorization vulnerability (CWE-862) in the Appointment Booking Calendar plugin for WordPress, specifically in versions up to 1.6.10.6. The vulnerability stems from a flawed authorization check in the nonce_permissions_check() method, which improperly validates requests using a public_nonce exposed via the /wp-json/ssa/v1/embed-inner endpoint. The plugin's appointment deletion endpoints accept requests with an X-WP-Nonce header and an X-PUBLIC-Nonce header. When the X-WP-Nonce validation fails, the function falls back to validating the X-PUBLIC-Nonce without rejecting the request. Since the public_nonce is site-wide and accessible to unauthenticated users, attackers can exploit this to view or delete arbitrary appointments by ID, compromising appointment confidentiality and integrity.
Potential Impact
An unauthenticated attacker can leverage this vulnerability to view sensitive appointment information, including public_edit_url details, delete arbitrary appointments, and modify booking records. This results in unauthorized disclosure of sensitive data, loss of appointment records, and potential disruption of the appointment booking service. The CVSS score of 6.5 (medium severity) reflects the network attack vector, low attack complexity, no privileges required, no user interaction, and impact on integrity and availability but no direct confidentiality impact.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. There is no official fix or patch information available at this time. Until a patch is released, users should consider disabling the affected plugin or restricting access to the vulnerable REST API endpoints to trusted users only. Monitor vendor channels for updates and apply official patches promptly once available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Wordfence
- Date Reserved
- 2026-03-25T12:28:32.101Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fc01afcbff5d86105e8a37
Added to database: 05/07/2026, 03:06:23 UTC
Last enriched: 05/14/2026, 03:48:49 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 274
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