CVE-2026-3427: Yoast SEO <= 27.1.1 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'jsonText' Block Attribute

Published Mar 22, 2026
·
Updated

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 input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Affected Software

1 affected component
Yoast Yoast SEO<=27.1.1

Event History

Mar 22, 2026
CVE Published
via MITRE·03:26 AM
Data Sourced
via MITRE·03:26 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·04:16 AM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is the severity of CVE-2026-3427?

CVE-2026-3427 is identified as a moderate severity vulnerability due to the potential for stored cross-site scripting attacks.

2

How do I fix CVE-2026-3427?

To fix CVE-2026-3427, update the Yoast SEO plugin to version 27.1.2 or later.

3

Who is affected by CVE-2026-3427?

CVE-2026-3427 affects all versions of the Yoast SEO plugin up to and including version 27.1.1.

4

What type of vulnerability is CVE-2026-3427?

CVE-2026-3427 is a stored cross-site scripting (XSS) vulnerability.

5

What is the impact of CVE-2026-3427 on users?

Users of vulnerable versions may face unauthorized script execution in their websites, leading to data theft or site defacement.

Company

Resources

Contact

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CVE-2026-3427 - Yoast SEO <= 27.1.1 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'jsonText' Block Attribute - SecAlerts