Yoast SEO <= 28.0 - Authenticated (Author+) Stored Cross-Site Scripting via Post Slug (post_name)

2026-07-24 17:58
Dmitrii Ignatyev

Vulnerability Overview

The Yoast SEO – Advanced SEO with real-time guidance and built-in AI plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Post Slug (post_name) in all versions up to, and including, 28.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires pretty permalinks to be enabled, as the exploit chain depends on get_permalink() embedding the stored percent-encoded post_name in the generated URL.

Technical Analysis

REMEDIATION: Update to version 28.1, or a newer patched version --- IDENTIFIER: CWE-79 (Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

External References

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C

Yoast SEO <= 28.0 - Authenticated (Author+) Stored Cross-Site Scripting via Post Slug (post_name) (CVE-2026-15425)