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Status published
High
CVE-2021-26036
[20210702] - Core - DoS through usergroup table manipulation
Vulnerability Description
An issue was discovered in Joomla! 2.5.0 through 3.9.27. Missing validation of input could lead to a broken usergroups table.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
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Affected Vendor
Joomla! Project
View all reports →Affected Software
Joomla! CMS
Vulnerable Versions:
2.5.0-3.9.27
Timeline
Official Publish:
July 7th, 2021
Last Modified:
February 25th, 2026
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.