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TI-2026-70138 Aliases CVE-2026-6723GHSA-3ppx-frf5-28p4

Incorrect authorization in Appointment Booking Calendar plugin

Priority LOW 29CWE-863Published · Updated

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

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00189 8th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

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

VendorProductAffected versionsFixed inStatusSource
croixhaugSimply Schedule Appointmentsup to 1.6.11.11—No fix listedCNA
  • Simply Schedule Appointments Vendorcroixhaug Affected up to 1.6.11.11 Fixed in — No fix listed CNA

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

  1. 2026-10-10 Threatist record created from CVE-2026-6723
  2. 2026-10-10 Alias added: GHSA-3ppx-frf5-28p4
  3. 2026-10-11 CISA SSVC decision points changed

References

  • 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
See all 43 →

Sources