Formidable Forms < 6.16.2 - Reflected Cross-Site Scripting via Custom HTML Form Parameter

Description

The plugin is vulnerable to POST-Based Reflected Cross-Site Scripting via the Custom HTML Form parameters due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers 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.