---
id: CVE-2026-104000
title: >-
  Simply Schedule Appointments <= 1.6.12.35 - Unauthenticated Stored Cross-Site
  Scripting via 'status' Parameter via /wp-json/ssa/v1/appointments/{id}
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. Thi…
severity: high
cvss: 7.2
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N'
cvssSource: cna
cwe:
  - CWE-79
vendor: croixhaug
product: Simply Schedule Appointments
affected:
  - simply_schedule_appointments <= 1.6.12.35
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-16T15:44:52.783850Z'
published: '2026-10-16'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:45:05.671Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-104000'
references:
  - url: >-
      https://www.wordfence.com/threat-intel/vulnerabilities/id/3a8bd422-112c-43bc-a041-3c6eea27b790?source=cve
  - url: >-
      https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-debug.php#L92
  - url: >-
      https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-appointment-model.php#L1490
  - url: >-
      https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.33/includes/class-utils.php#L716
  - url: >-
      https://plugins.trac.wordpress.org/changeset/3746344/simply-schedule-appointments/trunk/includes/class-appointment-model.php
tags:
  - cve.org
epss: 0.00236
epssPercentile: 0.13602
ingestedAt: '2026-10-16T06:00:00.394Z'
---

## Overview

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.

## Affected

- `simply_schedule_appointments <= 1.6.12.35`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.