[20260301] - Core - ACL hardening in com_ajax

Project: Joomla!
SubProject: CMS
Impact: Low
Severity: Low
Probability: Moderate
Versions: 3.0.0-5.4.3, 6.0.0-6.0.3
Exploit type: Incorrect Access Control
Reported Date: 2026-03-11
Fixed Date: 2026-03-31
CVE Number: CVE-2026-21629

Description

The ajax component was excluded from the default logged-in-user check in the administrative area. This behavior was potentially unexpected by 3rd party developers.

Affected Installs

Joomla! CMS versions 3.0.0-5.4.3, 6.0.0-6.0.3

Solution

Upgrade to version 5.4.4 or 6.0.4

Contact

The JSST at the Joomla! Security Centre.

Reported By: JSST