GHSA-QCFX-2MFW-W4CG

Vulnerability from github – Published: 2026-03-23 20:54 – Updated: 2026-05-13 16:15
VLAI
Summary
Rails Active Storage has possible content type bypass via metadata in direct uploads
Details

Impact

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.

Releases

The fixed releases are available at the normal locations.

Credit

This was responsible reported by Hackerone researcher pwnie

Severity
5.3 (Medium)
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
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{
  "affected": [
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "activestorage"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.1.0.beta1"
            },
            {
              "fixed": "8.1.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "activestorage"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0.beta1"
            },
            {
              "fixed": "8.0.4.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "activestorage"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.2.3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33173"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-925"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-23T20:54:16Z",
    "nvd_published_at": "2026-03-24T00:16:28Z",
    "severity": "MODERATE"
  },
  "details": "### Impact\nActive Storage\u0027s `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.\n\n### Releases\nThe fixed releases are available at the normal locations.\n\n### Credit\nThis was responsible reported by Hackerone researcher [pwnie](https://hackerone.com/pwnie)",
  "id": "GHSA-qcfx-2mfw-w4cg",
  "modified": "2026-05-13T16:15:54Z",
  "published": "2026-03-23T20:54:16Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/security/advisories/GHSA-qcfx-2mfw-w4cg"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33173"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/commit/707c0f1f41f067fdf96d54e99d43b28dfaae7e53"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/commit/8fcb934caadc79c8cc4ce53287046d0f67005b3e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/commit/d9502f5214e2198245a4c1defe9cd02a7c8057d0"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rails/rails"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/releases/tag/v7.2.3.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/releases/tag/v8.0.4.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rails/rails/releases/tag/v8.1.2.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/activestorage/CVE-2026-33173.yml"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Rails Active Storage has possible content type bypass via metadata in direct uploads"
}


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