Craft CMS - Authorization Bypass in assets/preview-file Endpoint
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass, Information disclosure
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-639 and CWE-200.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Craft CMS | cms | 5.0.0-RC1 to before 5.9.14; 4.0.0-RC1 to before 4.17.8 | 5.9.14, 4.17.8 | Patch available | CNA |
| — | craftcms/cms (Packagist) | 5.0.0-RC1 to before 5.9.14 | 5.9.14 | Patch available | GHSA-44px-qjjc-xrhq |
| — | craftcms/cms (Packagist) | 4.0.0-RC1 to before 4.17.8 | 4.17.8 | Patch available | GHSA-44px-qjjc-xrhq |
- cms VendorCraft CMS Affected 5.0.0-RC1 to before 5.9.14; 4.0.0-RC1 to before 4.17.8 Fixed in 5.9.14, 4.17.8 Patch available CNA
- craftcms/cms (Packagist) Vendor— Affected 5.0.0-RC1 to before 5.9.14 Fixed in 5.9.14 Patch available GHSA-44px-qjjc-xrhq
- craftcms/cms (Packagist) Vendor— Affected 4.0.0-RC1 to before 4.17.8 Fixed in 4.17.8 Patch available GHSA-44px-qjjc-xrhq
Remediation
- Fix · CNA cms (craftcms) Fixed in 5.9.14, 4.17.8
- Fix · GHSA-44px-qjjc-xrhq craftcms/cms (Packagist) Fixed in 5.9.14 Advisory →
- Fix · GHSA-44px-qjjc-xrhq craftcms/cms (Packagist) Fixed in 4.17.8 Advisory →
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
craftcms cms 4.17.8, 5.9.14
2 records Highest priority Priority LOW 2 LOW
Other records, highest priority first
- TI-2026-40747 Craft CMS - Missing Authorization in assets/preview-thumb EndpointPriority LOW 24
Timeline
- 2026-10-02 Threatist record created from CVE-2026-56385
- 2026-10-03 Alias added: GHSA-44px-qjjc-xrhq
References
More Craft CMS vulnerabilities
- TI-2025-23503 Craft CMS Allows Remote Code Execution KEVCVSS 3.1CRITICAL 10.0
- TI-2024-37138 RCE when PHP `register_argc_argv` config setting is enabled in craftcms/cms KEVCVSS 4.0CRITICAL 9.3
- TI-2025-16994 Potential RCE with a compromised security key in craft/cms KEVCVSS 3.1HIGH 8.1
- TI-2025-24595 Craft CMS stores user-provided content in session files KEVCVSS 4.0MEDIUM 6.9
- TI-2023-22284 Craft CMS Remote Code Execution vulnerability CVSS 3.1CRITICAL 10.0
- TI-2024-25171 Craft CMS up to v3.7.31 was discovered to contain a SQL injection vulnerability via the GraphQL API endpoint. CVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-56385 · CVE Program
- CVE-2026-56385 · NVD
- FIRST EPSS
- GHSA-44px-qjjc-xrhq · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences