The Fluent Forms WordPress plugin before 5.2.1 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).

The Freemius SDK, as used by hundreds of WordPress plugin and theme developers, was vulnerable to Cross-Site Request Forgery and Information disclosure due to missing capability checks and nonce protection on the _get_debug_log, _get_db_option, and the _set_db_option functions in versions up to, and including 2.4.2. Any WordPress plugin or theme running a version of Freemius less than 2.4.3 is vulnerable.

The Fluent Forms plugin for WordPress by Fluent Forms plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 5.1.9 due to insufficient input sanitization and output escaping. This makes it possible for attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The exploitation level depends on who is granted the right to create forms by an administrator. This level can be as low as contributor, but by default is admin.

The PDF Generator For Fluent Forms – The Contact Form Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the header, PDF body and footer content parameters in all versions up to, and including, 1.1.7 due to insufficient input sanitization and output escaping. This makes it possible for attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The exploitation level depends on who is granted the right to create forms by an administrator. This level can be as low as contributor, but by default is admin.