CVE-2026-6826

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

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

Configurations

Configuration 1 (hide)

cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-21 21:16

Updated : 2026-07-23 16:10

NVD link : CVE-2026-6826

Mitre link : CVE-2026-6826

CVE.ORG link : CVE-2026-6826

JSON object : View

Products Affected

concretecms

concrete_cms

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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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\u00a0CVSS: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\u00a0for reporting."}, {"lang": "es", "value": "Concrete CMS 9.5.0 y versiones anteriores es vulnerable a la divulgaci\u00f3n de uso de archivos no autenticada debido a la falta de una verificaci\u00f3n de permisos en el controlador de uso. Cualquier visitante no autenticado puede solicitar /ccm/system/dialogs/file/usage/{fID} con cualquier ID de archivo y recibir una lista de cada p\u00e1gina que hace referencia a ese archivo, incluyendo IDs de p\u00e1gina, identificadores y URLs completas. Esto incluye p\u00e1ginas que de otro modo estar\u00edan restringidas por permisos. El equipo de seguridad de Concrete CMS otorg\u00f3 a esta vulnerabilidad una puntuaci\u00f3n CVSS v.4.0 de 6.9 con el 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. Gracias Eldudareeno por informar."}], "lastModified": "2026-07-23T16:10:00.137", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2E0D5AA2-E073-464B-9026-9A428B24ABFA", "versionEndExcluding": "9.5.1"}], "operator": "OR"}]}], "sourceIdentifier": "ff5b8ace-8b95-4078-9743-eac1ca5451de"}