CVE-2026-104000 json
Simply Schedule Appointments <= 1.6.12.35 - Unauthenticated Stored Cross-Site Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id}
published 24d ago modified 24d ago also EUVD-2026-102663
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 14%
- public exploits
- 0
- none known
Summary
The Simply Schedule Appointments plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'status' parameter in all versions up to, and including, 1.6.12.35 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The malicious payload is stored unconditionally because debug logging is enabled by default, and the debug-log viewer is accessible to anyone holding the site-wide Support PIN (an HMAC-MD5 of AUTH_SALT displayed in wp-admin), meaning the injected script will execute against the administrator's session during ordinary support or troubleshooting workflows.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 24d ago
Exploit prediction
0.24% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- croixhaug Simply Schedule Appointments
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/3a8bd422-112c-43bc-a041-3c6eea27b790?source=cve
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-debug.php#L92
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-appointment-model.php#L1490
- plugins.trac.wordpress.org /browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-utils.php#L716
- plugins.trac.wordpress.org /changeset/3746344/simply-schedule-appointments/trunk/includes/class-appointment-model.php
Sources
- CVE List CVE-2026-104000
- NVD CVE-2026-104000
Fencer Intel 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.