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.

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
craftcms cms unaffected
Version Status Constraints
4.0.0-RC1 affected < 4.17.8
4.17.8 unaffected —
5.0.0-RC1 affected < 5.9.14
5.9.14 unaffected —

No data.

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Project Subscriptions

Vendors Products
Juzaweb Subscribe
Cms Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

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

Sun, 21 Jun 2026 15:00:00 +0000

Type Values Removed Values Added
Description 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.
Title Craft CMS - Missing Authorization in assets/preview-thumb Endpoint
First Time appeared Juzaweb
Juzaweb cms
Weaknesses CWE-862
CPEs cpe:2.3:a:juzaweb:cms:*:*:*:*:*:*:*:*
Vendors & Products Juzaweb
Juzaweb cms
References
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'}

cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-06-21T13:27:00.378Z

Reserved: 2026-06-21T02:05:47.495Z

Link: CVE-2026-56384

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses