CVE-2026-6826

MEDIUM

Concrete 9.5.0 and below has file usage disclosure via missing permission check in Usage controller

Title source: cna
STIX 2.1

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.

References (1)

Core 1

Scores

CVSS v3 5.3
EPSS 0.0025
EPSS Percentile 16.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-200
Status published
Products (2)
Concrete CMS/Concrete CMS 5.0 - 9.5.0
concretecms/concrete_cms < 9.5.1
Published May 21, 2026
Tracked Since May 22, 2026