# JCH Optimize <= 6.0.2 - Unauthenticated Stored Cross-Site Scripting via Host Header

- **ID:** WPSEC-2026-0773
- **Plugin:** JCH Optimize (`jch-optimize`), https://wordpress.org/plugins/jch-optimize/
- **Affected versions:** all versions before 6.1.0
- **Fixed in:** 6.1.0 (Update to 6.1.0 or later.)
- **Severity:** Medium 5.4 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N)
- **Weakness:** CWE-79
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-10-11)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/jch-optimize
- **Fix released:** 2026-10-10
- **Published:** 2026-10-11
- **URL:** https://wpsec.com/vuln/WPSEC-2026-0773/

## Description

The JCH Optimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Host header of requests stored by Page Cache in all versions up to, and including, 6.0.2, due to insufficient validation of the host name and insufficient output escaping of cached page URLs on the Page Cache list in the admin area. This makes it possible for unauthenticated attackers to inject arbitrary web scripts that execute when an administrator, or a user allowed to clear the page cache, views the Page Cache list. Exploitation requires Page Cache to be enabled and a web server that passes Host header values containing quote characters through to WordPress.

## References

- https://wpsec.com/vuln/WPSEC-2026-0773/
- https://plugins.svn.wordpress.org/jch-optimize/tags/6.1.0/
- https://wordpress.org/plugins/jch-optimize/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0773/

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.