Concretecms Concrete Cms
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.
What this means for your business
- It affects Concretecms Concrete Cms. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, without a login, but only after tricking someone into an action such as opening a file or a link.
- FIRST's prediction model gives it a 0.1% chance of attack attempts being seen in the next 30 days, ranking above 1% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Concretecms Concrete Cms, and which version. The affected versions are listed further down this page.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Fastnexa security experts
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Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N- CVSS v4
- 5.3
- Weakness
- CWE-352
- Assigned by
- ff5b8ace-8b95-4078-9743-eac1ca5451de
Dates
- Published
- 2026-09-11
- Last modified
- 2026-09-25
- Sources
- NVD
Affected products
- Concretecms Concrete Cms- 9.5.3
As listed in the NVD configuration data. Not a statement about your estate.