The Redux Framework plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Slider field in User Profile settings in versions up to and including 4.5.13.1. This is due to insufficient input sanitization in the usermetasave() function (which only sanitizes array values, not scalar values) and improper output escaping in the ReduxSlider::render() method, which outputs slider values into unquoted HTML attributes. The vulnerability also exploits the fact that the cleandefault() method only casts values to numeric types when they are empty or out of bounds, allowing malicious strings like '1 tabindex=0 autofocus onfocus=alert(1) x=' to pass validation through PHP's loose type comparison. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject arbitrary web scripts into their user profile that will execute whenever an Administrator navigates to view the attacker's profile page.

The Redux Framework plugin for WordPress is vulnerable to unauthenticated JSON file uploads due to missing authorization and capability checks on the ReduxColorSchemeImport function in versions 4.4.12 to 4.4.17. This makes it possible for unauthenticated attackers to upload JSON files, which can be used to conduct stored cross-site scripting attacks and, in some rare cases, when the wpfilesystem fails to initialize - to Remote Code Execution.