CVE-2026-33173
Published: Mar 23, 2026
Modified: Mar 24, 2026
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.
| Vendor | Product | Versions |
|---|---|---|
rails | activestorage | affected >= 8.1.0.beta1, < 8.1.2.1affected >= 8.0.0.beta1, < 8.0.4.1affected < 7.2.3.1 |
Weaknesses (CWE)
References
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