The Bold Page Builder WordPress plugin before 5.9.8 does not sanitise and escape several shortcode attributes before outputting them in HTML attributes, allowing users with the Contributor role and above to inject arbitrary web scripts that execute when a user views the affected page.

The Bold Page Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's btbbaccordionitem shortcode in all versions up to, and including, 5.6.1 due to insufficient input sanitization and output escaping on user supplied attributes. 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.