CVE-2026-6826
Description
Concrete CMS 9.5.0 and below is vulnerable to unauthenticated file usage disclosure via missing permission check in the usage controller. Any unauthenticated visitor can request /ccm/system/dialogs/file/usage/{fID} with any file ID and receive a list of every page that references that file, including page IDs, handles, and full URLs. This includes pages that are otherwise restricted by permissions.The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.9 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Eldudareeno for reporting.
How to fix
- concretecms concrete_cms9.5.1 or later
- concrete5/concrete59.5.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| concretecms concrete_cms | v < 9.5.1 | 9.5.1 |
| concrete5/concrete5Packagist | v < 9.5.1 | 9.5.1 |
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Attack Surface Management
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