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.
Exploitability
AV:NAC:LPR:LUI:NScope
S:CImpact
C:LI:LA:N6.4/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:NInjection