Appointment Booking Calendar <= 1.6.11.11 — Incorrect Authorization to Unauthenticated Sensitive Field Modification via Appointment Public Token
CVE-2026-6723Published · Updated Action summary
Affected: ≤1.6.11.11Update to 1.6.12.0 or newer
All remediation steps- Severity
- Medium5.3
- CVSS
- 5.3CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NWhat does this vector mean?
AV:NAttack vector- Network
AC:LAttack complexity- Low
PR:NPrivileges required- None
UI:NUser interaction- None
S:UScope- Unchanged
C:NConfidentiality- None
I:LIntegrity- Low
A:NAvailability- None
- Weakness
- CWE-863 Incorrect Authorization
- Required access
- No account needed
- Exploit prediction (EPSS)
- No score
- CISA KEV
- Not listed
On this page8
Am I affected?
Simply Schedule Appointments simply-schedule-appointments
- Affected≤ 1.6.11.11
- Patched in1.6.12.0
Update to 1.6.12.0 or newer.
You are affected if you run ≤ 1.6.11.11. Version 1.6.12.0 and later are not affected by this issue.
- Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Simply Schedule Appointments.
- No admin access? Run a passive check of your site. It reads public files only.
- No account is needed to exploit this. Treat any exposed site on an affected version as at risk.
What to do
- Update to version 1.6.12.0, or a newer patched version
- Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
- Watch Simply Schedule Appointments to get an email when the next vulnerability is published.
Advisory
Source description from Wordfence Intelligence, credited to awhacken.
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.
Exploits & references
Proof-of-concept & detection
No public proof-of-concept or detection template is known for this vulnerability.
Advisories & patches
- Advisorywordfence.com
Related CVEs
More in Simply Schedule Appointments
All 52| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| Medium5.3 | Missing Authorization ≤1.6.13.0Update to 1.6.13.4 | CVE-2026-125437 | |
| High7.2 | Unauthenticated Stored Cross-Site Scripting ≤1.6.12.35Update to 1.6.12.37 | CVE-2026-110382 | |
| Medium4.3 | Authenticated (Contributor+) Insecure Direct Object Reference ≤1.6.12.35Update to 1.6.12.37 | CVE-2026-110381 | |
| High7.2 | Unauthenticated Stored Cross-Site Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id} ≤1.6.12.35Update to 1.6.12.37 | CVE-2026-104000 | |
| Medium6.5 | Insecure Direct Object Reference to Authenticated (Subscriber+) Sensitive Information Disclosure via 'complete_group' Parameter ≤1.6.12.31Update to 1.6.12.33 | CVE-2026-91109 |
- Medium5.3Missing Authorization
≤1.6.13.0Update to 1.6.13.4
- High7.2Unauthenticated Stored Cross-Site Scripting
≤1.6.12.35Update to 1.6.12.37
- Medium4.3Authenticated (Contributor+) Insecure Direct Object Reference
≤1.6.12.35Update to 1.6.12.37
- High7.2Unauthenticated Stored Cross-Site Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id}
≤1.6.12.35Update to 1.6.12.37
- Medium6.5Insecure Direct Object Reference to Authenticated (Subscriber+) Sensitive Information Disclosure via 'complete_group' Parameter
≤1.6.12.31Update to 1.6.12.33
Timeline
CVE published
Severity medium, CVSS 5.3
Record last updated
Sources & licenses
Wordfence record- Vulnerability data
- Wordfence Intelligence. [object Object] Licensed under the CC BY-SA 4.0.
- CVE® identifiers
- [object Object]. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
- CVSS / CWE
- National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
- VulnCrest content
- Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.
