CVE-2026-6937 json
Appointment Booking Calendar <= 1.6.11.8 - Missing Authorization to Unauthenticated Arbitrary Modification via Bulk Appointments REST API Endpoint
published 2026-05-28 5 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-32747
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 46%
- public exploits
- 0
- none known
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.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 5 mo ago
Exploit prediction
0.56% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected products
- croixhaug Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin
Classification
- Weakness
-
- CWE-862 Missing Authorization
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/ef0f5f9d-788a-4cf8-9747-ada076a69a1f?source=cve
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/trunk/includes/class-bootstrap.php#L151
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/trunk/includes/lib/td-util/class-td-api-model.php#L74
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.11.0/includes/lib/td-util/class-td-api-model.php#L74
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/trunk/includes/class-appointment-model.php#L724
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-appointment-model.php#L724
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.11.0/includes/class-bootstrap.php#L151
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.10.0/includes/lib/td-util/class-td-api-model.php#L74
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.10.0/includes/class-appointment-model.php#L724
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.10.0/includes/class-bootstrap.php#L151
- plugins.trac.wordpress.org /changeset?sfp_email=&sfph_mail=&reponame=&old=3549843%40simply-schedule-appointments&new=3549843%40simply-sch
Sources
- CVE List CVE-2026-6937
- NVD CVE-2026-6937
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.