[20260514] – Core – Privilege escalation through com_users webservice endpoints

• Project: Joomla!
• SubProject: CMS
• Impact: High
• Severity: Moderate
• Probability: Low
• Versions: 4.0.0-5.4.5,6.0.0-6.1.0
• Exploit type: Privilege Escalation
• Reported Date: 2026-04-15
• Fixed Date: 2026-05-26
• CVE Number: CVE-2026-48904

Description

An improper access check allows privelege escalation through the com_users group editing webservice endpoint.

Affected Installs

Joomla! CMS versions 4.0.0-5.4.5,6.0.0-6.1.0

Solution

Upgrade to version 5.4.6,6.1.1

Contact

The JSST at the Joomla! Security Centre.

Reported By:  Christos Papakonstantinou, Cantina