What is CVE-2026-13400?

CVE-2026-13400 is a medium-severity vulnerability in Simply Schedule Appointments, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-07-27.

How severe is CVE-2026-13400?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Simply Schedule Appointments

CVE-2026-13400

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 int…

Vulnerability class: XSS (Cross-Site Scripting)

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Unknown Simply Schedule Appointments — versions 0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

contact@wpscan.com (technical-description, exploit, vdb-entry)

Frequently asked questions

What is CVE-2026-13400?: CVE-2026-13400 is a medium-severity vulnerability in Simply Schedule Appointments, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-07-27.
How severe is CVE-2026-13400?: Medium severity. CVSS v3 base score is 6.1 out of 10.