USN-8733-2 (UBUNTU-CVE-2026-41991)

Vulnerability from osv_ubuntu – Published: 2026-09-22 16:04 – Updated: 2026-09-22 16:04 – Source website
VLAI
Summary
gzip vulnerabilities
Details

USN-8733-1 fixed vulnerabilities in Gzip. This update provides the corresponding fix for Gzip on Ubuntu 14.04 LTS, Ubuntu 18.04 LTS and Ubuntu 20.04 LTS.

Original advisory details:

Michał Majchrowicz and Marcin Wyczechowski discovered that Gzip's gzexe utility created temporary files in an insecure manner when mktemp was unavailable. A local attacker could possibly use this issue to overwrite arbitrary files. (CVE-2026-41991)

Elias Hasas, Michał Majchrowicz and Marcin Wyczechowski discovered that Gzip incorrectly handled certain compressed files. An attacker could possibly use this issue to obtain sensitive information or cause Gzip to crash, resulting in a denial of service. (CVE-2026-41992)

References
To clipboard 

{
  "affected": [
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-41991",
              "severity": [
                {
                  "score": "CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-41992",
              "severity": [
                {
                  "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:14.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "gzip",
            "binary_version": "1.6-3ubuntu1+esm2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:14.04:LTS",
        "name": "gzip",
        "purl": "pkg:deb/ubuntu/gzip@1.6-3ubuntu1+esm2?arch=source\u0026distro=esm-infra-legacy/trusty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.6-3ubuntu1+esm2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.6-2ubuntu1",
        "1.6-3ubuntu1",
        "1.6-3ubuntu1+esm1"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-41991",
              "severity": [
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                  "score": "CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
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                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-41992",
              "severity": [
                {
                  "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:18.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "gzip",
            "binary_version": "1.6-5ubuntu1.2+esm1"
          },
          {
            "binary_name": "gzip-win32",
            "binary_version": "1.6-5ubuntu1.2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "gzip",
        "purl": "pkg:deb/ubuntu/gzip@1.6-5ubuntu1.2+esm1?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
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            },
            {
              "fixed": "1.6-5ubuntu1.2+esm1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.6-5ubuntu1",
        "1.6-5ubuntu1.1",
        "1.6-5ubuntu1.2"
      ]
    },
    {
      "database_specific": {
        "cves_map": {
          "cves": [
            {
              "id": "CVE-2026-41991",
              "severity": [
                {
                  "score": "CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            },
            {
              "id": "CVE-2026-41992",
              "severity": [
                {
                  "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
                  "type": "CVSS_V4"
                },
                {
                  "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                  "type": "CVSS_V3"
                },
                {
                  "score": "medium",
                  "type": "Ubuntu"
                }
              ]
            }
          ],
          "ecosystem": "Ubuntu:Pro:20.04:LTS"
        }
      },
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "gzip",
            "binary_version": "1.10-0ubuntu4.1+esm1"
          },
          {
            "binary_name": "gzip-win32",
            "binary_version": "1.10-0ubuntu4.1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "gzip",
        "purl": "pkg:deb/ubuntu/gzip@1.10-0ubuntu4.1+esm1?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
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            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.10-0ubuntu3",
        "1.10-0ubuntu4",
        "1.10-0ubuntu4.1"
      ]
    }
  ],
  "aliases": [],
  "details": "USN-8733-1 fixed vulnerabilities in Gzip. This update provides the\ncorresponding fix for Gzip on Ubuntu 14.04 LTS, Ubuntu 18.04 LTS and Ubuntu\n20.04 LTS.\n\nOriginal advisory details:\n\n Micha\u0142 Majchrowicz and Marcin Wyczechowski discovered that Gzip\u0027s gzexe\nutility created temporary files in an insecure manner when mktemp was\nunavailable. A local attacker could possibly use this issue to overwrite\narbitrary files. (CVE-2026-41991)\n\n Elias Hasas, Micha\u0142 Majchrowicz and Marcin Wyczechowski discovered that\nGzip incorrectly handled certain compressed files. An attacker could\npossibly use this issue to obtain sensitive information or cause Gzip to\ncrash, resulting in a denial of service. (CVE-2026-41992)",
  "id": "USN-8733-2",
  "modified": "2026-09-22T16:04:21Z",
  "published": "2026-09-22T16:04:21Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8733-2"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-41991"
    },
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-41992"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "summary": "gzip vulnerabilities",
  "upstream": [
    "UBUNTU-CVE-2026-41991",
    "UBUNTU-CVE-2026-41992"
  ]
}



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