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 - The mail template feature lacks an escaping mechanism, causing XSS vectors in multiple extensions.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://developer.joomla.org/security-centre/1088-20260908-core-xss-in-html-mail-templates.html	Patch Vendor Advisory
https://www.joomla.org/	Product

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:joomla:joomla\!::::::::
	cpe:2.3:a:joomla:joomla\!::::::::

History

06 Oct 2026, 16:35

Type	Values Removed	Values Added
First Time		Joomla joomla\! Joomla
References	~~() https://developer.joomla.org/security-centre/1088-20260908-core-xss-in-html-mail-templates.html -~~	() https://developer.joomla.org/security-centre/1088-20260908-core-xss-in-html-mail-templates.html - Patch, Vendor Advisory
References	~~() https://www.joomla.org/ -~~	() https://www.joomla.org/ - Product
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3
CPE		cpe:2.3:a:joomla:joomla\!::::::::

29 Sep 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-29 17:17

Updated : 2026-10-06 16:35

NVD link : CVE-2026-90918

Mitre link : CVE-2026-90918

CVE.ORG link : CVE-2026-90918

JSON object : View

Products Affected

joomla

joomla\!

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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