CVE-2026-33173
published 2026-03-24CVE-2026-33173: 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`…
medium5.3CVSS 4.0
AVNACLATNPRNUIPVCNVILVANSCNSINSANEXCRXIRXARXMAVXMACXMATXMPRXMUIXMVCXMVIXMVAXMSCXMSIXMSAXSXAUXRXVXREXUX
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.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | rails | — | — |
| rails | activestorage | < 7.2.3.1 | 7.2.3.1 |
| rails | activestorage | — | — |
| rails | activestorage | — | — |
| rails | activestorage | >= 0 < 7.2.3.1 | 7.2.3.1 |
| rails | activestorage | >= 8.0.0.beta1 < 8.0.4.1 | 8.0.4.1 |
| rails | activestorage | >= 8.1.0.beta1 < 8.1.2.1 | 8.1.2.1 |
| rubyonrails | rails | < 7.2.3.1 | 7.2.3.1 |
| rubyonrails | rails | >= 8.0.0 < 8.0.4.1 | 8.0.4.1 |
| rubyonrails | rails | >= 8.1.0 < 8.1.2.1 | 8.1.2.1 |
CVSS provenance
nvdv4.05.3MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
osv5.3MEDIUM