NEX-Forms < 9.2.3 - Unauthenticated Stored Cross-Site Scripting via 'real_val__' Parameter

Description

The NEX-Forms – Ultimate Forms Plugin for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'real_val__' parameter in all versions up to, and including, 9.2.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The submission endpoint is registered via wp_ajax_nopriv_submit_nex_form with no nonce verification, making it fully accessible to unauthenticated attackers without any CSRF token.