CVE-2026-6826CWE-200

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

Medium · published May 21, 2026

CVSS v4.0
6.9
EPSS
1%
Percentile
69.8
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
6.9 · MEDIUM
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
EPSS
0.01282 · 69.8th percentile
Weakness
CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor
Published
2026-05-21T20:55Z
EPSS history
Timeline
  • 21 MAY 20:55Z
    Concrete 9.5.0 and below has file usage disclosure via missing permission check in Usage controller
    cvelistv5