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GHSA-M42X-37P3-FV5W

Vulnerability from github – Published: 2020-05-26 15:09 – Updated: 2023-07-05 19:19
VLAI
Summary
Circumvention of file size limits in ActiveStorage
Details

There is a vulnerability in ActiveStorage's S3 adapter that allows the Content-Length of a direct file upload to be modified by an end user.

Versions Affected: rails < 5.2.4.2, rails < 6.0.3.1 Not affected: Applications that do not use the direct upload functionality of the ActiveStorage S3 adapter. Fixed Versions: rails >= 5.2.4.3, rails >= 6.0.3.1

Impact

Utilizing this vulnerability, an attacker can control the Content-Length of an S3 direct upload URL without receiving a new signature from the server. This could be used to bypass controls in place on the server to limit upload size.

Workarounds

This is a low-severity security issue. As such, no workaround is necessarily until such time as the application can be upgraded.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 5.2.4.2"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "activestorage"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.0.0"
            },
            {
              "fixed": "5.2.4.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 6.0.3"
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "activestorage"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.0.0"
            },
            {
              "fixed": "6.0.3.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-8162"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434",
      "CWE-602"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2020-05-26T15:06:42Z",
    "nvd_published_at": "2020-06-19T17:15:00Z",
    "severity": "HIGH"
  },
  "details": "There is a vulnerability in ActiveStorage\u0027s S3 adapter that allows the Content-Length of a direct file upload to be modified by an end user.\n\nVersions Affected:  rails \u003c 5.2.4.2, rails \u003c 6.0.3.1\nNot affected:       Applications that do not use the direct upload functionality of the ActiveStorage S3 adapter.\nFixed Versions:     rails \u003e= 5.2.4.3, rails \u003e= 6.0.3.1\n\nImpact\n------\n\nUtilizing this vulnerability, an attacker can control the Content-Length of an S3 direct upload URL without receiving a new signature from the server. This could be used to bypass controls in place on the server to limit upload size.\n\nWorkarounds\n-----------\n\nThis is a low-severity security issue. As such, no workaround is necessarily until such time as the application can be upgraded.",
  "id": "GHSA-m42x-37p3-fv5w",
  "modified": "2023-07-05T19:19:29Z",
  "published": "2020-05-26T15:09:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-8162"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aws/aws-sdk-ruby/issues/2098"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/789579"
    },
    {
      "type": "WEB",
      "url": "https://github.com/aws/aws-sdk-ruby"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/activestorage/CVE-2020-8162.yml"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/forum/#!topic/rubyonrails-security/PjU3946mreQ"
    },
    {
      "type": "WEB",
      "url": "https://groups.google.com/g/rubyonrails-security/c/PjU3946mreQ"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2020/dsa-4766"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Circumvention of file size limits in ActiveStorage"
}



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