Concrete CMS up to 9.5.2 Calendar Duplicate Dialog duplicate.php submit cross-site request forgery

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Concrete CMS up to 9.5.2. The affected element is the function Submit of the file concrete/controllers/dialog/event/duplicate.php of the component Calendar Duplicate Dialog. This manipulation causes cross-site request forgery. The identification of this vulnerability is CVE-2026-68526. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Concrete CMS up to 9.5.2 and classified as problematic. Affected by this vulnerability is the function submit of the file concrete/controllers/dialog/event/duplicate.php of the component Calendar Duplicate Dialog. The manipulation with an unknown input leads to a cross-site request forgery vulnerability. The CWE definition for the vulnerability is CWE-352. The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request. As an impact it is known to affect integrity. The summary by CVE is:

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.

The advisory is shared at documentation.concretecms.org. This vulnerability is known as CVE-2026-68526 since 07/30/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

By approaching the search of inurl:concrete/controllers/dialog/event/duplicate.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 9.5.3 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Content Management System

Name

• Concrete CMS

Version

• 9.5.0
• 9.5.1
• 9.5.2

License

• open-source

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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