Missing authorization in croixhaug Appointment Booking Calendar — Simply Schedule…
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-862.
Summary
The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 1.6.11.8 due to the plugin not properly verifying that a user is authorized to perform an action via the bulk appointments REST API endpoint. This makes it possible for unauthenticated attackers to modify arbitrary appointment records including customer PII, payment status, and meeting URL fields, and to expose full customer PII from existing appointment records via the bulk endpoint response. The public nonce is a static, user-independent value present in the HTML source of any page hosting the [ssa_booking] shortcode, meaning any visitor who has viewed such a page can obtain it and target any appointment in the system without authentication.
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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| croixhaug | Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin | up to 1.6.11.8 | — | No fix listed | CNA |
- Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin Vendorcroixhaug Affected up to 1.6.11.8 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-6937
- 2026-10-03 Alias added: GHSA-4cp9-7xpg-wmvc
References
Other 11
- https://www.wordfence.com/threat-intel/vulnerabilities/id/ef0f5f9d-788a-4cf8-9747-ada076a69a1f?source=cve
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/trunk/includes/class-bootstrap.php#L151
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/trunk/includes/lib/td-util/class-td-api-model.php#L74
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/lib/td-util/class-td-api-model.php#L74
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/trunk/includes/class-appointment-model.php#L724
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-appointment-model.php#L724
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-bootstrap.php#L151
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.10.0/includes/lib/td-util/class-td-api-model.php#L74
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.10.0/includes/class-appointment-model.php#L724
- https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.10.0/includes/class-bootstrap.php#L151
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3549843%40simply-schedule-appointments&new=3549843%40simply-schedule-appointments&sfp_email=&sfph_mail=
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-2026-6937 · CVE Program
- CVE-2026-6937 · NVD
- FIRST EPSS
- GHSA-4cp9-7xpg-wmvc · 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