The BigBlueButton plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the the moderator code and viewer code fields in versions up to, and including, 3.0.0-beta.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers with author privileges or higher to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.