CVE-2026-8236 PUBLISHED

Concrete CMS 9.5.0 and below is vulnerable to IDOR combined with a missing authentication gate for endpoint /ccm/system/dialogs/file/usage/{fID}

Assigner: ConcreteCMS
Reserved: 09.05.2026 Published: 21.05.2026 Updated: 22.05.2026

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.

Metrics

CVSS 4.0

CVSS 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
CVSS Score: 6.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	Low	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	Present	Availability	None	Availability	None
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	Concrete CMS
Product	Concrete CMS
Versions	Default: unaffected affected from 5 to 9.5.0 (incl.)

Credits

Winston Crooker finder

References

https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes

Problem Types

CWE-862 CWE

Impacts

CAPEC-116 Excavation