CVE-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` 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 products

Rails, Red Os

Rubyonrails Rails

< 7.2.3.1, 8.0.4.1, 8.1.2.1

Fix

Available

CVSS 3.1

5.3 MEDIUM

EPSS

0.4% (32th percentile)

Weakness

CWE-925

NVD status

Analyzed

Published

2026-03-23

No exploit for CVE-2026-33173 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.