CVE-2026-104000CWE-79cross-site-scripting

CVE-2026-104000

High · published October 16, 2026

CVSS v3.1
7.2
EPSS
0%
Percentile
13.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.2 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00236 · 13.9th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2026-10-16T10:17Z
References (5)
https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-debug.php#L92 · [email protected]https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-utils.php#L716 · [email protected]https://plugins.trac.wordpress.org/changeset/3746344/simply-schedule-appointments/trunk/includes/class-appointment-model.php · [email protected]https://www.wordfence.com/threat-intel/vulnerabilities/id/3a8bd422-112c-43bc-a041-3c6eea27b790?source=cve · [email protected]https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-appointment-model.php#L1490 · [email protected]
EPSS history
Timeline
  • 17 OCT 03:27Z
    EPSS moved — → 0%
    epss
  • 16 OCT 05:30Z
    Simply Schedule Appointments <= 1.6.12.35 - Unauthenticated Stored Cross-Site Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id}
    cvelistv5
  • 16 OCT 05:30Z
    Simply Schedule Appointments <= 1.6.12.35 - Unauthenticated Stored Cross-Site Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id}
    cvelistv5