Back to overview

CVE-2026-13400

MEDIUM Exploitation: PoC
6.1
CVSS 3.1
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.

Metadata

CVE ID
CVE-2026-13400
State
PUBLISHED
Assigner
WPScan
Reserved
2026-06-26 08:35 UTC
Published
2026-07-27 06:00 UTC
Last updated
2026-07-27 13:53 UTC
Primary CWE
CWE-79
CWE-79 Improper Neutralization of Input During Web Page Gene…
Vendor / Product
Unknown / Simply Schedule Appointments
Sources
cve.org  ·  NVD

Severity & Metrics

6.1 MEDIUM CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC — CISA Coordinator
Exploitation
PoC
Automatable
no
Tech. Impact
partial
Affected products (1)
VendorProductPlatformVersions
Unknown Simply Schedule Appointments — 0 < 1.6.12.4
Weakness (CWE)
CWESourceDescription
— cna CWE-79 Cross-Site Scripting (XSS)
CWE-79 adp CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVSS scores (1)
ScoreSeverityVersionSourceVector
6.1 MEDIUM 3.1 adp CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
References (1)
Back to overview