Add Custom Body Class <= 1.4.1 - Authenticated (Contributor+) Stored Cross-Site Scripting

The Add Custom Body Class plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'add_custom_body_class' value in versions up to, and including, 1.4.1 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.