The Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Notification Smartcode Values in all versions up to, and including, 6.2.11 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts that execute in the browser of an administrator (or any user with the Fluent Forms entry-viewing capability) when they view the form's entry Submission Logs in the WordPress admin dashboard. Exploitation requires that a site administrator or Fluent Forms manager has configured an email notification whose subject or static (direct) Send To value references an attacker-influenced Smartcode such as an inputpassword field value, a cookie value, or submission.response.
The Fluent Forms plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the form-submission.js script in all versions up to, and including, 6.0.2 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.
The Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder plugin for WordPress is vulnerable to IP Address Spoofing in all versions up to, and including, 5.2.12 due to insufficient IP address validation and use of user-supplied HTTP headers as a primary method for IP retrieval. This makes it possible for unauthenticated attackers spoof their IP address and submit forms that may have IP-based restrictions.
The Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder plugin for WordPress is vulnerable to PHP Object Injection in versions 5.1.16 to 6.1.1 via deserialization of untrusted input in the parseUserProperties function. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject a PHP Object. The additional presence of a POP chain allows attackers to read arbitrary files. If allowurlinclude is enabled on the server, remote code execution is possible. While the vendor patched this issue in version 6.1.0, the patch caused a fatal error in the vulnerable code, due to a missing class import, so we consider 6.1.2 to be the most complete and best patched version