High severity · published Apr 1, 2026
CVE-2026-21629
Joomla! Core - [20260301] - ACL hardening in com_ajax
7.3
CVSS
0.2%
EPSS
No
On KEV
Description
The ajax component was excluded from the default logged-in-user check in the administrative area. This behavior was potentially unexpected by 3rd party developers.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 16% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JO
Joomla · Joomla
3.0.0-5.4.3; 6.0.0-6.0.3 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21629
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21629
Vendor Advisory
https://developer.joomla.org/security-centre/1027-20260301-core-acl-hardening-in-com-ajax.html
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