CVE-2026-68526

Concrete CMS before 9.5.3 did not validate an anti-CSRF token in the Calendar event duplicate dialog controller (concrete/controllers/dialog/event/duplicate.php) submit() action, which duplicated a calendar event after checking only canAccess() and the per-resource canAddCalendarEvent() permission, so a crafted cross-site request could cause an authenticated user with add-event permission to create duplicate CalendarEvents and CalendarEventVersions records under their own authority. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.3 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://documentation.concretecms.org/9-x/developers/introduction/version-history/953-release-notes	Release Notes

Configurations

Configuration 1 (hide)

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

History

25 Sep 2026, 20:41

Type	Values Removed	Values Added
CPE		cpe:2.3:a:concretecms:concrete_cms::::::::
First Time		Concretecms Concretecms concrete Cms
References	~~() https://documentation.concretecms.org/9-x/developers/introduction/version-history/953-release-notes -~~	() https://documentation.concretecms.org/9-x/developers/introduction/version-history/953-release-notes - Release Notes
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 4.3

Information

Published : 2026-09-11 20:17

Updated : 2026-09-25 20:41

NVD link : CVE-2026-68526

Mitre link : CVE-2026-68526

CVE.ORG link : CVE-2026-68526

JSON object : View

Products Affected

concretecms

concrete_cms

CWE

CWE-352

Cross-Site Request Forgery (CSRF)

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