[20260708] - Core - XSS through language overrides

Project: Joomla!
SubProject: CMS
Impact: Moderate
Severity: Moderate
Probability: Low
Versions: 3.0.0-5.4.6,6.0.0-6.1.1
Exploit type: XSS
Reported Date: 2026-05-15
Fixed Date: 2026-07-07
CVE Number: CVE-2026-48954

Description

Improper validation leads to a generic XSS vector in the language override feature.

Affected Installs

Joomla! CMS versions 3.0.0-5.4.5,6.0.0-6.1.1

Solution

Upgrade to version 5.4.7, 6.1.2

Contact

The JSST at the Joomla! Security Centre.

Reported By: Morris Baumgarten-Egemole