Description
Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, `DirectUploadsController` accepts arbitrary metadata from the client and persists it on the blob. Because internal flags like `identified` and `analyzed` are stored in the same metadata hash, a direct-upload client can set these flags to skip MIME detection and analysis. This allows an attacker to upload arbitrary content while claiming a safe `content_type`, bypassing any validations that rely on Active Storage's automatic content type identification. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.
Metrics
CVSS 3.1 5.3/10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| rails | activestorage | >= 8.1.0.beta1, < 8.1.2.1; >= 8.0.0.beta1, < 8.0.4.1; < 7.2.3.1 |
References
- https://github.com/rails/rails/commit/707c0f1f41f067fdf96d54e99d43b28dfaae7e53Patch
- https://github.com/rails/rails/commit/8fcb934caadc79c8cc4ce53287046d0f67005b3ePatch
- https://github.com/rails/rails/commit/d9502f5214e2198245a4c1defe9cd02a7c8057d0Patch
- https://github.com/rails/rails/releases/tag/v7.2.3.1Release Notes
- https://github.com/rails/rails/releases/tag/v8.0.4.1Release Notes
- https://github.com/rails/rails/releases/tag/v8.1.2.1Release Notes
- https://github.com/rails/rails/security/advisories/GHSA-qcfx-2mfw-w4cgVendor Advisory
Timeline
- Published
- Mar 24, 2026
- Last modified
- Jun 17, 2026
- NVD status
- Analyzed