WP All Export Pro <= 1.9.1 - Unauthenticated Remote Code Execution via Custom Export Fields

The WP ALL Export Pro plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 1.9.1 via the custom export fields. This is due to the missing input validation and sanitization of user-supplied data. This makes it possible for unauthenticated attackers to inject arbitrary PHP code into form fields that get executed on the server during the export, potentially leading to a complete site compromise. As a prerequisite, the custom export field should include fields containing user-supplied data.