The FiboSearch – Ajax Search for WooCommerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'purchased_plan' parameter in all versions up to, and including, 1.34.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Exploitation requires that the site owner has previously completed the standard Freemius opt-in flow; once that condition is met, any Subscriber can reach the vulnerable handler simply by loading /wp-admin/profile.php with the requisite query parameters.