ubuntu-cve-2021-41816
Vulnerability from osv_ubuntu
Published
2021-12-02 00:00
Modified
2026-04-22 07:40
Summary
Details

CGI.escape_html in Ruby before 2.7.5 and 3.x before 3.0.3 has an integer overflow and resultant buffer overflow via a long string on platforms (such as Windows) where size_t and long have different numbers of bytes. This also affects the CGI gem before 0.3.1 for Ruby.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libruby2.7",
            "binary_version": "2.7.0-5ubuntu1.6"
          },
          {
            "binary_name": "ruby2.7",
            "binary_version": "2.7.0-5ubuntu1.6"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "ruby2.7",
        "purl": "pkg:deb/ubuntu/ruby2.7@2.7.0-5ubuntu1.6?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.7.0-5ubuntu1.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.7.0-1",
        "2.7.0-2",
        "2.7.0-3",
        "2.7.0-4",
        "2.7.0-4ubuntu1",
        "2.7.0-5ubuntu1",
        "2.7.0-5ubuntu1.1",
        "2.7.0-5ubuntu1.2",
        "2.7.0-5ubuntu1.3",
        "2.7.0-5ubuntu1.4",
        "2.7.0-5ubuntu1.5"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libruby3.0",
            "binary_version": "3.0.2-7ubuntu2"
          },
          {
            "binary_name": "ruby3.0",
            "binary_version": "3.0.2-7ubuntu2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "ruby3.0",
        "purl": "pkg:deb/ubuntu/ruby3.0@3.0.2-7ubuntu2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.2-7ubuntu2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.0.2-5ubuntu1",
        "3.0.2-7"
      ]
    }
  ],
  "aliases": [],
  "details": "CGI.escape_html in Ruby before 2.7.5 and 3.x before 3.0.3 has an integer overflow and resultant buffer overflow via a long string on platforms (such as Windows) where size_t and long have different numbers of bytes. This also affects the CGI gem before 0.3.1 for Ruby.",
  "id": "UBUNTU-CVE-2021-41816",
  "modified": "2026-04-22T07:40:10Z",
  "published": "2021-12-02T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-41816"
    },
    {
      "type": "REPORT",
      "url": "https://www.ruby-lang.org/en/news/2021/11/24/buffer-overrun-in-cgi-escape_html-cve-2021-41816/"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/ruby/cgi/commit/c728632c1c09d46cfd4ecbff9caaa3651dd1002a"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-5235-1"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-41816"
    }
  ],
  "related": [
    "USN-5235-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-41816"
  ]
}



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