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.
References1
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 17 · as of 13 November 2026
- CWE
- CWE-79
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