Medium severity · published Apr 1, 2026
CVE-2026-21631
Joomla! Core - [20260303] - XSS vector in com_associations comparison view
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
Lack of output escaping leads to a XSS vector in the multilingual associations component.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 12% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JO
Joomla · Joomla
4.0.0-5.4.3; 6.0.0-6.0.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21631
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21631
Vendor Advisory
https://developer.joomla.org/security-centre/1029-20260303-core-xss-vector-in-com-associations-comparison-view.html
Exploit
https://github.com/Shirshaw64p/security-advisories/tree/main/CVE-2026-21631
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