CVE-2026-33173: Rails Active Storage has possible content type bypass via metadata in direct uploads
(updated )
Active Storage’s 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 malicious direct-upload client could set these flags.
References
- github.com/advisories/GHSA-qcfx-2mfw-w4cg
- github.com/rails/rails
- github.com/rails/rails/commit/707c0f1f41f067fdf96d54e99d43b28dfaae7e53
- github.com/rails/rails/commit/8fcb934caadc79c8cc4ce53287046d0f67005b3e
- github.com/rails/rails/commit/d9502f5214e2198245a4c1defe9cd02a7c8057d0
- github.com/rails/rails/releases/tag/v7.2.3.1
- github.com/rails/rails/releases/tag/v8.0.4.1
- github.com/rails/rails/releases/tag/v8.1.2.1
- github.com/rails/rails/security/advisories/GHSA-qcfx-2mfw-w4cg
- nvd.nist.gov/vuln/detail/CVE-2026-33173
Code Behaviors & Features
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