What’s Vulnerable › Vulnerabilities
CVE-2026-6826: Concrete 9.5.0 and below has file usage disclosure via missing permission check in Usage controller
- Severity: medium (CVSS 5.3 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.5% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2026-05-21 · updated 2026-07-23
- Weakness: CWE-200
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.
Affected products
- Concrete CMS: before 9.5.1 — fixed in 9.5.1
How to fix
Upgrade to a fixed version: Concrete CMS 9.5.1. Check the vendor advisory for mitigations.
References
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