CVE-2026-90918: Joomla! Core - [20260908] - Core - XSS in HTML Mail Templates in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3

Published Sep 29, 2026
·
Updated

Joomla! Core - [20260908] - Core - XSS in HTML Mail Templates in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3 - The mail template feature lacks an escaping mechanism, causing XSS vectors in multiple extensions.

Affected Software

1 affected component
Joomla joomla>=4.0.0<=5.4.8, >=6.0.0<=6.1.3

Event History

Sep 29, 2026
CVE Published
via MITRE·04:38 PM
Data Sourced
via MITRE·04:38 PM
DescriptionWeakness
Data Sourced
via NVD·05:17 PM
DescriptionSeverityWeakness

Frequently Asked Questions

1

Which Joomla versions are affected?

Affected versions are Joomla 4.0.0 through 5.4.8 and Joomla 6.0.0 through 6.1.3.

2

What component is involved in this issue?

The issue affects the HTML mail template feature in Joomla Core. The lack of an escaping mechanism creates XSS vectors in multiple extensions.

Contact

SecAlerts Pty Ltd.
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Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
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