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GHSA-GH9Q-2XRM-X6QV

Vulnerability from github – Published: 2025-03-03 20:53 – Updated: 2025-11-04 00:32
VLAI
Summary
CGI has Denial of Service (DoS) potential in Cookie.parse
Details

There is a possibility for DoS by in the cgi gem. This vulnerability has been assigned the CVE identifier CVE-2025-27219. We recommend upgrading the cgi gem.

Details

CGI::Cookie.parse took super-linear time to parse a cookie string in some cases. Feeding a maliciously crafted cookie string into the method could lead to a Denial of Service.

Please update CGI gem to version 0.3.5.1, 0.3.7, 0.4.2 or later.

Affected versions

cgi gem versions <= 0.3.5, 0.3.6, 0.4.0 and 0.4.1.

Credits

Thanks to lio346 for discovering this issue. Also thanks to mame for fixing this vulnerability.

Severity
5.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "cgi"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.3.5.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "cgi"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.3.6"
            },
            {
              "fixed": "0.3.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.3.6"
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "cgi"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.4.0"
            },
            {
              "fixed": "0.4.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-27219"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-03-03T20:53:43Z",
    "nvd_published_at": "2025-03-04T00:15:31Z",
    "severity": "MODERATE"
  },
  "details": "There is a possibility for DoS by in the cgi gem.\nThis vulnerability has been assigned the CVE identifier CVE-2025-27219. We recommend upgrading the cgi gem.\n\n## Details\n\nCGI::Cookie.parse took super-linear time to parse a cookie string in some cases. Feeding a maliciously crafted cookie string into the method could lead to a Denial of Service.\n\nPlease update CGI gem to version 0.3.5.1, 0.3.7, 0.4.2 or later.\n\n## Affected versions\n\ncgi gem versions \u003c= 0.3.5, 0.3.6, 0.4.0 and 0.4.1.\n\n## Credits\n\nThanks to lio346 for discovering this issue.\nAlso thanks to mame for fixing this vulnerability.",
  "id": "GHSA-gh9q-2xrm-x6qv",
  "modified": "2025-11-04T00:32:21Z",
  "published": "2025-03-03T20:53:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-27219"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ruby/cgi/pull/52"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ruby/cgi/pull/53"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ruby/cgi/pull/54"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/2936778"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ruby/cgi"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/cgi/CVE-2025-27219.yml"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00008.html"
    },
    {
      "type": "WEB",
      "url": "https://www.cve.org/CVERecord?id=CVE-2025-27219"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "CGI has Denial of Service (DoS) potential in Cookie.parse"
}



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