CVE-2026-81912

Concrete CMS before 9.5.3 is vulnerable to Cross-Site Request Forgery in the Move Multiple Groups feature. The dashboard/users/groups/bulkupdate/confirm() endpoint moved the selected group tree nodes without validating an action token, so a state-changing group move could be processed for an authenticated user who did not initiate it. Because relocating a group under a new parent causes that group's members to inherit the parent's permissions, a forged move can change effective authorization. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.7 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks riodrwn for reporting.

CVSS v3 5.7 MEDIUM

5.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.1 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes	Broken Link

Configurations

Configuration 1 (hide)

cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*

History

24 Sep 2026, 20:18

Type	Values Removed	Values Added
References	~~() https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes -~~	() https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes - Broken Link
CPE		cpe:2.3:a:concretecms:concrete_cms::::::::
First Time		Concretecms Concretecms concrete Cms
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.7

Information

Published : 2026-09-11 20:19

Updated : 2026-09-24 20:18

NVD link : CVE-2026-81912

Mitre link : CVE-2026-81912

CVE.ORG link : CVE-2026-81912

JSON object : View

Products Affected

concretecms

concrete_cms

CWE

CWE-352

Cross-Site Request Forgery (CSRF)

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