CVE-2026-8236
Concrete CMS is vulnerable to IDOR combined with a missing authentication gate
EPSS 0.20%
Description
Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate. The endpoint /ccm/system/dialogs/file/usage/{fID} accepts an integer file ID in the URL and returns internal site structure data (page IDs, versions, URL paths) to anyone who sends a GET request.
How to fix CVE-2026-8236
To remediate CVE-2026-8236, upgrade the affected package to a fixed version below.
- Packagist/concrete5/concrete5—upgrade to 9.5.1 or later
Is CVE-2026-8236 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 9.5.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |