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. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector 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. Thanks Winston Crooker for reporting.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Concrete CMS | Concrete CMS | — | — |
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- Concrete CMS <9.5.1 - Unauthenticated File-Usage Internal Metadata Disclosure http/cves/2026/CVE-2026-8236.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Packagist | concrete5/concrete5 | < 9.5.1 | 9.5.1 | GHSA-58c8-vvqw-cm7m |