USN-4692-1 (UBUNTU-CVE-2018-20482)

Vulnerability from osv_ubuntu – Published: 2021-01-13 18:56 – Updated: 2026-06-29 10:52 – Source website
VLAI
Summary
tar vulnerabilities
Details

Chris Siebenmann discovered that tar incorrectly handled extracting files resized during extraction when invoked with the --sparse flag. An attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 12.04 ESM, Ubuntu 14.04 ESM, Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2018-20482)

Daniel Axtens discovered that tar incorrectly handled certain malformed tar files. If a user or automated system were tricked into processing a specially crafted tar archive, a remote attacker could use this issue to cause tar to crash, resulting in a denial of service. (CVE-2019-9923)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2018-20482",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2019-9923",
              "severity": [
                {
                  "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:14.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "tar",
            "binary_version": "1.27.1-1ubuntu0.1+esm1"
          },
          {
            "binary_name": "tar-scripts",
            "binary_version": "1.27.1-1ubuntu0.1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "tar",
        "purl": "pkg:deb/ubuntu/tar@1.27.1-1ubuntu0.1+esm1?arch=source\u0026distro=trusty/esm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.27.1-1ubuntu0.1+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.26+dfsg-8",
        "1.27-3",
        "1.27-4",
        "1.27.1-1",
        "1.27.1-1ubuntu0.1"
      ]
    },
    {
      "database_specific": {
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            {
              "id": "CVE-2018-20482",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2019-9923",
              "severity": [
                {
                  "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:16.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "tar",
            "binary_version": "1.28-2.1ubuntu0.2"
          },
          {
            "binary_name": "tar-scripts",
            "binary_version": "1.28-2.1ubuntu0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "tar",
        "purl": "pkg:deb/ubuntu/tar@1.28-2.1ubuntu0.2?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.28-2.1ubuntu0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.27.1-2",
        "1.28-2ubuntu1",
        "1.28-2.1",
        "1.28-2.1ubuntu0.1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2018-20482",
              "severity": [
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2019-9923",
              "severity": [
                {
                  "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:18.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "tar",
            "binary_version": "1.29b-2ubuntu0.2"
          },
          {
            "binary_name": "tar-scripts",
            "binary_version": "1.29b-2ubuntu0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "tar",
        "purl": "pkg:deb/ubuntu/tar@1.29b-2ubuntu0.2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.29b-2ubuntu0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.29b-2",
        "1.29b-2ubuntu0.1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2019-9923",
              "severity": [
                {
                  "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                  "type": "CVSS_V3"
                },
                {
                  "score": "low",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:20.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "tar",
            "binary_version": "1.30+dfsg-7ubuntu0.20.04.1"
          },
          {
            "binary_name": "tar-scripts",
            "binary_version": "1.30+dfsg-7ubuntu0.20.04.1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "tar",
        "purl": "pkg:deb/ubuntu/tar@1.30+dfsg-7ubuntu0.20.04.1?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.30+dfsg-7ubuntu0.20.04.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.30+dfsg-6",
        "1.30+dfsg-7"
      ]
    }
  ],
  "aliases": [],
  "details": "Chris Siebenmann discovered that tar incorrectly handled extracting files\nresized during extraction when invoked with the --sparse flag. An attacker\ncould possibly use this issue to cause a denial of service. This issue\nonly affected Ubuntu 12.04 ESM, Ubuntu 14.04 ESM, Ubuntu 16.04 LTS and\nUbuntu 18.04 LTS. (CVE-2018-20482)\n\nDaniel Axtens discovered that tar incorrectly handled certain malformed\ntar files. If a user or automated system were tricked into processing a\nspecially crafted tar archive, a remote attacker could use this issue to\ncause tar to crash, resulting in a denial of service. (CVE-2019-9923)\n",
  "id": "USN-4692-1",
  "modified": "2026-06-29T10:52:48Z",
  "published": "2021-01-13T18:56:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-4692-1"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2018-20482"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2019-9923"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "tar vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2018-20482",
    "UBUNTU-CVE-2019-9923"
  ]
}



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