CVE-2026-5399

Description

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 user_meta_save() function (which only sanitizes array values, not scalar values) and improper output escaping in the Redux_Slider::render() method, which outputs slider values into unquoted HTML attributes. The vulnerability also exploits the fact that the clean_default() 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.

References

• https://github.com/reduxframework/redux-framework/pull/4112/changes
• https://plugins.trac.wordpress.org/browser/redux-framework/tags/4.5.10/redux-core/inc/extensions/users/class-redux-extension-users.php#L1018
• https://plugins.trac.wordpress.org/browser/redux-framework/tags/4.5.10/redux-core/inc/fields/slider/class-redux-slider.php#L311
• https://plugins.trac.wordpress.org/browser/redux-framework/trunk/redux-core/inc/extensions/users/class-redux-extension-users.php#L1018
• https://plugins.trac.wordpress.org/browser/redux-framework/trunk/redux-core/inc/fields/slider/class-redux-slider.php#L311