The Groundhogg plugin for Wordpress is vulnerable to Stored Cross-Site Scripting via the ‘label' parameter in versions up to, and including, 3.7.4.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Administrator-level access, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.
https://plugins.trac.wordpress.org/changeset/3264477/
https://plugins.trac.wordpress.org/browser/groundhogg/trunk/assets/js/admin/forms/form-builder-v2.js
https://github.com/groundhoggwp/groundhogg/commit/5206bf2482e2fe210ccca6e7dcfe62ffe85b3061