High severity · published Aug 18, 2026
CVE-2026-71573
Joomla! Core - [20260802] - Improper CORS origin validation in Joomla 4.0.0-5.4.7, 6.0.0-6.1.2
8.3
CVSS
0.3%
EPSS
No
On KEV
Description
Joomla! Core - [20260802] - Improper CORS origin validation in Joomla 4.0.0-5.4.7, 6.0.0-6.1.2 - An improper implementation prevented configured CORS origins from being properly validated in CORS requests.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JO
Joomla · Joomla
4.0.0-5.4.6; 6.0.0-6.1.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-71573
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-71573
Vendor Advisory
https://developer.joomla.org/security-centre/20260802-core-improper-cors-origin-validation.html
Product
https://www.joomla.org/
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