XSS in Yoast Seo – Advanced With Real-time Guidance And Built-in Ai

CVE-2026-3427

The Yoast SEO – Advanced SEO with real-time guidance and built-in AI plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the the `jsonText` block attribute in all versions up to, and including, 27.1.1 due to insufficient…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.000 (15.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-3427?
CVE-2026-3427 is a medium-severity vulnerability in Yoast Seo – Advanced With Real-time Guidance And Built-in Ai, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-03-22.
How severe is CVE-2026-3427?
Medium severity. CVSS v3 base score is 6.4 out of 10.