VULNERABILITY INTELLIGENCE

CVE-2026-13400

CVSS score6.1 MEDIUM
EPSS probability0.25%
CISA KEVNot currently listed
Published2026-07-27
Last modified2026-07-27
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Description

Simply Schedule Appointments is vulnerable to unauthenticated Stored Cross-Site Scripting in all versions up to and including 1.6.12.2. The root cause is a sanitization-ordering defect: the rendered notification content is decoded back into live HTML after it has already passed through the Simply Schedule Appointments WordPress plugin before 1.6.12.4's wp_kses_post() filter, so a double-encoded payload survives intake and is reintroduced as an executable element at render time.

Weakness classification

  • 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-79

Primary references