What the vulnerability does
01Description
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.
Explanation of Vulnerability in Simple Terms
02Summary
Yoast SEO versions up to 27.1.1 contain a cross-site scripting vulnerability that allows authenticated users to inject malicious scripts affecting other site visitors. The vulnerability has a changed scope, meaning the impact extends beyond the plugin itself to the broader site. Low-privileged users can exploit this without additional user interaction.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that execute in other users' browsers when they visit the site.
Potential impact on your site
04Site Impact
Visitors and administrators may have their sessions hijacked, credentials stolen, or be redirected to malicious sites.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege account (e.g., contributor or editor role) on the WordPress site.
Key dates
06Disclosure timeline
March 22, 2026
CVE published
April 8, 2026
Record updated
