Description
Concrete CMS 9.5.0 and below is vulnerable to missing authorization in the bulk_user_assignment.php which can lead to privilege escalation to Administrative Group. Any authenticated user with access to the bulk user assignment dashboard page can add any user email to any group and can remove legitimate admins. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 7.5 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Vincent55 for reporting.
References (1)
Core 1
Core References
Release Notes release-notes
https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes
Scores
CVSS v3
8.8
EPSS
0.0030
EPSS Percentile
21.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-863
Status
published
Products (2)
Concrete CMS/Concrete CMS
5.0 - 9.5.0
concretecms/concrete_cms
< 9.5.0
Published
May 21, 2026
Tracked Since
May 22, 2026