CVE-2026-56385: Craft CMS - Authorization Bypass in assets/preview-file Endpoint
Craft CMS versions >= 5.0.0-RC1, <= 5.9.13 and >= 4.0.0-RC1, <= 4.17.7 contain an authorization bypass in the assets/preview-file endpoint. The action does not enforce per-asset view authorization before returning preview content, allowing an authenticated low-privileged user to supply a controlled assetId for an asset they are not permitted to view and still receive preview response data (previewHtml), including a private preview image route containing the target private assetId. Fixed in 5.9.14 and 4.17.8.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Craft CMSto a version that resolves this vulnerability.Fixed in 5.9.14 - Upgrade
Upgrade
Craft CMSto a version that resolves this vulnerability.Fixed in 4.17.8
Event History
Frequently Asked Questions
What is CVE-2026-56385?
CVE-2026-56385 is a vulnerability in Craft CMS that allows an authenticated low-privileged user to bypass authorization and access unauthorized asset preview content.
What are the affected versions for CVE-2026-56385?
CVE-2026-56385 affects Craft CMS versions >= 5.0.0-RC1, <= 5.9.13 and >= 4.0.0-RC1, <= 4.17.7.
How do I fix CVE-2026-56385?
To fix CVE-2026-56385, update Craft CMS to version 5.9.14 or 4.17.8 or later, which includes the necessary authorization enforcement.
What is the severity level of CVE-2026-56385?
CVE-2026-56385 has a medium severity level of 4.3 on the CVSS scale.
What impact does CVE-2026-56385 have on user data?
CVE-2026-56385 may allow low-privileged users to view unauthorized preview content, potentially compromising sensitive information.