The Oxygen Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via a custom field in all versions up to, and including, 4.8 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. NOTE: Version 4.8.1 of the Oxygen Builder plugin for WordPress addresses this vulnerability by implementing an optional filter to provide output escaping for dynamic data. Please see https://oxygenbuilder.com/documentation/other/security/#filtering-dynamic-data for more details.