Concrete CMS up to 9.5.2 Calendar Event Edit Dialog edit.php authorization

Summaryinfo

A vulnerability marked as problematic has been reported in Concrete CMS up to 9.5.2. The impacted element is an unknown function of the file concrete/controllers/dialog/event/edit.php of the component Calendar Event Edit Dialog. Performing a manipulation results in authorization. This vulnerability is cataloged as CVE-2026-68527. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in Concrete CMS up to 9.5.2. It has been classified as problematic. This affects an unknown code of the file concrete/controllers/dialog/event/edit.php of the component Calendar Event Edit Dialog. The manipulation with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Concrete CMS versions 8.3.0 through 9.5.2 are vulnerable to an authorization bypass in the Calendar event edit dialog (concrete/controllers/dialog/event/edit.php). The dialog checked permissions against the calendar identifier supplied in the request rather than the calendar owning the targeted event occurrence. A user with the "Add Event" permission on a single calendar could read and overwrite events on calendars they were not permitted to access, and could delete an event's original local occurrence. Publishing the injected version to the live calendar, which demotes the previously approved version, additionally required the actor's approve_calendar_event workflow rights or an auto-approving workflow. The Concrete CMS Security Team gave this a rank of 5.9 with CVSS 4.0 vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.

The advisory is shared at documentation.concretecms.org. This vulnerability is uniquely identified as CVE-2026-68527 since 07/30/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are needed for exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/10/2026).

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

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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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If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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