The Advanced Sermons plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘sermon_video_embed’ parameter in all versions up to, and including, 3.3 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.
https://plugins.trac.wordpress.org/changeset/3147283/
https://plugins.trac.wordpress.org/browser/advanced-sermons/trunk/admin/meta/sermon-details.php#L396