Incorrect authorization in Appointment Booking Calendar plugin
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-863.
Summary
The Appointment Booking Calendar WordPress plugin by croixhaug is affected in all versions up to and including 1.6.11.11. Its appointment update REST API endpoint does not restrict which fields token-authenticated customers can modify, an incorrect authorization flaw (CWE-863). An unauthenticated attacker can change admin-controlled appointment fields, such as faking payment confirmation, reassigning the appointment to another user, or changing the service type.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Incorrect Authorization in all versions up to, and including, 1.6.11.11. This is due to the appointment update REST API endpoint not restricting which fields can be modified by token-authenticated customers. This makes it possible for unauthenticated attackers to modify admin-controlled fields on that appointment, including faking payment confirmation, reassigning the appointment to another user, and changing the service type.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
The sources list no fixed version for the Appointment Booking Calendar plugin.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Timeline
- 2026-10-10 Threatist record created from CVE-2026-6723
- 2026-10-10 Alias added: GHSA-3ppx-frf5-28p4
- 2026-10-11 CISA SSVC decision points changed
References
More croixhaug vulnerabilities
- TI-2026-46678 WordPress Simply Schedule Appointments plugin <= 1.6.12.10 - SQL Injection vulnerability CVSS 3.1CRITICAL 9.3
- TI-2026-28467 WordPress Simply Schedule Appointments plugin <= 1.6.9.27 - SQL Injection vulnerability CVSS 3.1CRITICAL 9.3
- TI-2026-06865 Appointment Booking Calendar <= 1.6.11.8 - Unauthenticated SQL Injection via 'append_where_sql' Parameter CVSS 3.1HIGH 7.5
- TI-2026-62275 Missing authorization in croixhaug Simply Schedule Appointments CVSS 3.1HIGH 7.5
- TI-2026-58265 WordPress Simply Schedule Appointments plugin <= 1.6.12.23 - Cross Site Request Forgery (CSRF) vulnerability CVSS 3.1HIGH 8.8
- TI-2026-30684 WordPress Simply Schedule Appointments plugin < 1.6.11.2 - Sensitive Data Exposure vulnerability CVSS 3.1HIGH 7.5
Sources
- CVE-2026-6723 · CVE Program
- CVE-2026-6723 · NVD
- FIRST EPSS
- GHSA-3ppx-frf5-28p4 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences