USN-6483-1 (UBUNTU-CVE-2021-33391)

Vulnerability from osv_ubuntu – Published: 2023-11-15 14:31 – Updated: 2026-04-27 14:11 – Source website
VLAI
Summary
tidy-html5 vulnerability
Details

Neeraj Pal discovered that HTML Tidy incorrectly handled parsing certain HTML data. If a user or automated system were tricked into parsing specially crafted HTML data, a remote attacker could cause HTML Tidy to consume resources, leading to a denial of service, or possibly execute arbitrary code.

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-33391",
              "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": "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"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:20.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libtidy5deb1",
            "binary_version": "2:5.6.0-11ubuntu0.20.04.1"
          },
          {
            "binary_name": "tidy",
            "binary_version": "2:5.6.0-11ubuntu0.20.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "tidy-html5",
        "purl": "pkg:deb/ubuntu/tidy-html5@2:5.6.0-11ubuntu0.20.04.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2:5.6.0-11ubuntu0.20.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2:5.6.0-10",
        "2:5.6.0-11"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2021-33391",
              "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": "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"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:22.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libtidy5deb1",
            "binary_version": "2:5.6.0-11ubuntu0.22.04.1"
          },
          {
            "binary_name": "tidy",
            "binary_version": "2:5.6.0-11ubuntu0.22.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "tidy-html5",
        "purl": "pkg:deb/ubuntu/tidy-html5@2:5.6.0-11ubuntu0.22.04.1?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2:5.6.0-11ubuntu0.22.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2:5.6.0-11build1",
        "2:5.6.0-11build2"
      ]
    }
  ],
  "aliases": [],
  "details": "Neeraj Pal discovered that HTML Tidy incorrectly handled parsing certain\nHTML data. If a user or automated system were tricked into parsing\nspecially crafted HTML data, a remote attacker could cause HTML Tidy to\nconsume resources, leading to a denial of service, or possibly execute\narbitrary code.\n",
  "id": "USN-6483-1",
  "modified": "2026-04-27T14:11:31Z",
  "published": "2023-11-15T14:31:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-6483-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-33391"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "tidy-html5 vulnerability",
  "upstream": [
    "UBUNTU-CVE-2021-33391"
  ]
}



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