CVE-2026-33173

MEDIUM EPSS 30.9%
Published Mar 24, 20263mo ago · Modified Jun 17, 20262w ago
5.3 CVSS 4.0
Medium
Find Similar
Published Mar 24, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago

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.

CVSS Details

Base Score
5.3
Exploitability
—
Impact
—
Vector string
CVSS: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
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction P
Scope X

Threat Intelligence

EPSS Exploit Probability
30.9% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-925

Affected Products 3

VendorProductVersionRange
rubyonrailsrails* <7.2.3.1
rubyonrailsrails*≥8.0.0  –  <8.0.4.1
rubyonrailsrails*≥8.1.0  –  <8.1.2.1

References 7

  • github.com https://github.com/rails/rails/commit/707c0f1f41f067fdf96d54e99d43b28dfaae7e53
    Patch
  • github.com https://github.com/rails/rails/commit/8fcb934caadc79c8cc4ce53287046d0f67005b3e
    Patch
  • github.com https://github.com/rails/rails/commit/d9502f5214e2198245a4c1defe9cd02a7c8057d0
    Patch
  • github.com https://github.com/rails/rails/releases/tag/v7.2.3.1
    Release Notes
  • github.com https://github.com/rails/rails/releases/tag/v8.0.4.1
    Release Notes
  • github.com https://github.com/rails/rails/releases/tag/v8.1.2.1
    Release Notes
  • github.com https://github.com/rails/rails/security/advisories/GHSA-qcfx-2mfw-w4cg
    Vendor Advisory

Remediation

  • github.com https://github.com/rails/rails/commit/707c0f1f41f067fdf96d54e99d43b28dfaae7e53
    Patch
  • github.com https://github.com/rails/rails/commit/8fcb934caadc79c8cc4ce53287046d0f67005b3e
    Patch
  • github.com https://github.com/rails/rails/commit/d9502f5214e2198245a4c1defe9cd02a7c8057d0
    Patch