Concretecms Concrete Cms
CVE-2026-68535
Concrete CMS Area API's block-create endpoint in versions 9.2.0 to 9.5.2 did not invoke the block type controller's validate() method on submitted data, which, for file-referencing blocks such as hero_image and gallery, is where the referenced file is authorized against the user's file-manager visibility. As a result, an authenticated user holding the block-add scope could store, and cause the page to render, a reference to a file that the file-manager authorization policy would otherwise reject, disclosing that file's URL and preview to the editor and to visitors of the affected page. Under public file storage, the URL and thumbnail are exposed directly; under private storage, the disclosure is limited by the permission-checked download URL. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 5.1 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N. Thanks riodrwn 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, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 20% 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.
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Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N- CVSS v4
- 5.1
- Weakness
- CWE-862
- Assigned by
- ff5b8ace-8b95-4078-9743-eac1ca5451de
Dates
- Published
- 2026-09-11
- Last modified
- 2026-09-24
- Sources
- NVD
Affected products
- Concretecms Concrete Cms9.2.0 - 9.5.3
As listed in the NVD configuration data. Not a statement about your estate.