ElementsKit Elementor Addons and Templates <= 3.5.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via Custom Widget

The ElementsKit Elementor Addons and Templates plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the URL attribute of a custom widget in all versions up to, and including, 3.5.2 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.