# Master Slider <= 3.11.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via ms_slider Shortcode Attributes

- **ID:** WPSEC-2026-0436
- **Plugin:** Master Slider – Responsive Touch Slider (`master-slider`), https://wordpress.org/plugins/master-slider/
- **Affected versions:** all versions before 3.11.3
- **Fixed in:** 3.11.3 (Update to 3.11.3 or later.)
- **Severity:** Medium 6.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N)
- **Weakness:** CWE-79
- **Usage among sites WPSec scans:** plugin Medium, affected versions Medium (as of 2026-10-06)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/master-slider
- **Fix released:** 2026-10-05
- **Published:** 2026-10-06
- **URL:** https://wpsec.com/vuln/WPSEC-2026-0436/

## Description

The Master Slider plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'ms_slider' shortcode's layout, fill_mode, layers_mode, direction, parallax_mode and view attributes in all versions up to, and including, 3.11.2 due to insufficient input sanitization and output escaping when these values are echoed into an inline JavaScript block. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

## References

- https://wpsec.com/vuln/WPSEC-2026-0436/
- https://plugins.svn.wordpress.org/master-slider/tags/3.11.3/
- https://wordpress.org/plugins/master-slider/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0436/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.