CVE-2026-56384

Craft CMS contains a missing authorization vulnerability in the assets/preview-thumb endpoint. A Control Panel user without permission to view a target private asset can call the endpoint with an attacker-controlled assetId and receive preview HTML containing a signed fallback transform preview link for that private asset, because no asset-view permission check is performed before preview generation. This affects versions >= 4.0.0-RC1, <= 4.17.7 and >= 5.0.0-RC1, <= 5.9.13, and is fixed in 4.17.8 and 5.9.14.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/craftcms/cms/commit/d30df3112220db1ffd6726a3ed11857014c7fb27
https://github.com/craftcms/cms/security/advisories/GHSA-x76w-8c62-48mg
https://www.vulncheck.com/advisories/craft-cms-missing-authorization-in-assets-preview-thumb-endpoint

Configurations

No configuration.

History

21 Jun 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-21 14:16

Updated : 2026-06-22 18:41

NVD link : CVE-2026-56384

Mitre link : CVE-2026-56384

CVE.ORG link : CVE-2026-56384

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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