[20260519] – Framework – Inadequate content filtering within the checkAttribute filter code

• Project: Joomla!
• SubProject: Framewok
• Impact: Moderate
• Severity: Moderate
• Probability: Moderate
• Versions: 3.0.0-5.4.5,6.0.0-6.1.0
• Exploit type: XSS
• Reported Date: 2026-04-21
• Fixed Date: 2026-05-26
• CVE Number: CVE-2026-48903

Description

Inadequate content filtering within the checkAttribute methods leads to XSS vulnerabilities in various components.

Affected Installs

Joomla! CMS versions 3.0.0-5.4.5,6.0.0-6.1.0

Solution

Upgrade to version 5.4.6,6.1.1

Contact

The JSST at the Joomla! Security Centre.

Reported By:  JSST