The Ninja Forms Contact Form WordPress plugin before 3.6.13 unserialises the content of an imported file, which could lead to PHP object injections issues when an admin import (intentionally or not) a malicious file and a suitable gadget chain is present on the blog.
The Ninja Forms Contact Form WordPress plugin before 3.6.10 does not sanitise and escape field labels, allowing high privilege users to perform Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed.
The Ninja Forms Contact Form WordPress plugin before 3.6.10 does not sanitize and escape some imported data, allowing high privilege users to perform Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed.
The Ninja Forms Contact Form WordPress plugin before 3.6.4 does not escape keys of the fields POST parameter, which could allow high privilege users to perform SQL injections attacks