CVE-2026-21631

Lack of output escaping leads to a XSS vector in the multilingual associations component.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://developer.joomla.org/security-centre/1029-20260303-core-xss-vector-in-com-associations-comparison-view.html	Vendor Advisory
https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-21631	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

09 Apr 2026, 19:55

Type	Values Removed	Values Added
First Time		Joomla Joomla joomla\!
CPE		cpe:2.3:a:joomla:joomla\!::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.4
References	~~() https://developer.joomla.org/security-centre/1029-20260303-core-xss-vector-in-com-associations-comparison-view.html -~~	() https://developer.joomla.org/security-centre/1029-20260303-core-xss-vector-in-com-associations-comparison-view.html - Vendor Advisory
References	~~() https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-21631 -~~	() https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-21631 - Exploit, Third Party Advisory

01 Apr 2026, 20:16

Type	Values Removed	Values Added
References		() https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-21631 -

01 Apr 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-01 10:16

Updated : 2026-04-09 19:55

NVD link : CVE-2026-21631

Mitre link : CVE-2026-21631

CVE.ORG link : CVE-2026-21631

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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