UBUNTU-CVE-2026-5745 (CVE-2026-5745)

Vulnerability from osv_ubuntu – Published: 2026-04-07 16:16 – Updated: 2026-07-22 23:16 – Source website
VLAI
Details

A flaw was found in libarchive. A NULL pointer dereference vulnerability exists in the ACL parsing logic, specifically within the archive_acl_from_text_nl() function. When processing a malformed ACL string (such as a bare "d" or "default" tag without subsequent fields), the function fails to perform adequate validation before advancing the pointer. An attacker can exploit this by providing a maliciously crafted archive, causing an application utilizing the libarchive API (such as bsdtar) to crash, resulting in a Denial of Service (DoS).

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "libarchive-tools",
            "binary_version": "3.4.0-2ubuntu1.5+esm3"
          },
          {
            "binary_name": "libarchive13",
            "binary_version": "3.4.0-2ubuntu1.5+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "libarchive",
        "purl": "pkg:deb/ubuntu/libarchive@3.4.0-2ubuntu1.5+esm3?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.4.0-2ubuntu1.5+esm3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.4.0-1",
        "3.4.0-1build1",
        "3.4.0-1ubuntu2",
        "3.4.0-2ubuntu1",
        "3.4.0-2ubuntu1.1",
        "3.4.0-2ubuntu1.2",
        "3.4.0-2ubuntu1.3",
        "3.4.0-2ubuntu1.4",
        "3.4.0-2ubuntu1.5",
        "3.4.0-2ubuntu1.5+esm1",
        "3.4.0-2ubuntu1.5+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libarchive-tools",
            "binary_version": "3.6.0-1ubuntu1.8"
          },
          {
            "binary_name": "libarchive13",
            "binary_version": "3.6.0-1ubuntu1.8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "libarchive",
        "purl": "pkg:deb/ubuntu/libarchive@3.6.0-1ubuntu1.8?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.6.0-1ubuntu1.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.4.3-2",
        "3.4.3-2build1",
        "3.5.2-1",
        "3.5.2-1ubuntu1",
        "3.6.0-1ubuntu1",
        "3.6.0-1ubuntu1.1",
        "3.6.0-1ubuntu1.2",
        "3.6.0-1ubuntu1.3",
        "3.6.0-1ubuntu1.4",
        "3.6.0-1ubuntu1.5",
        "3.6.0-1ubuntu1.6",
        "3.6.0-1ubuntu1.7"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libarchive-tools",
            "binary_version": "3.7.2-2ubuntu0.8"
          },
          {
            "binary_name": "libarchive13t64",
            "binary_version": "3.7.2-2ubuntu0.8"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "libarchive",
        "purl": "pkg:deb/ubuntu/libarchive@3.7.2-2ubuntu0.8?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.7.2-2ubuntu0.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.6.2-1ubuntu1",
        "3.7.2-1ubuntu1",
        "3.7.2-1ubuntu2",
        "3.7.2-1.1ubuntu2",
        "3.7.2-2",
        "3.7.2-2ubuntu0.1",
        "3.7.2-2ubuntu0.2",
        "3.7.2-2ubuntu0.3",
        "3.7.2-2ubuntu0.4",
        "3.7.2-2ubuntu0.5",
        "3.7.2-2ubuntu0.6",
        "3.7.2-2ubuntu0.7"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libarchive-tools",
            "binary_version": "3.7.7-0ubuntu3.2"
          },
          {
            "binary_name": "libarchive13t64",
            "binary_version": "3.7.7-0ubuntu3.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "libarchive",
        "purl": "pkg:deb/ubuntu/libarchive@3.7.7-0ubuntu3.2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.7.7-0ubuntu2",
        "3.7.7-0ubuntu2.1",
        "3.7.7-0ubuntu2.2",
        "3.7.7-0ubuntu3",
        "3.7.7-0ubuntu3.1",
        "3.7.7-0ubuntu3.2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libarchive-tools",
            "binary_version": "3.8.5-1ubuntu2.2"
          },
          {
            "binary_name": "libarchive13t64",
            "binary_version": "3.8.5-1ubuntu2.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "libarchive",
        "purl": "pkg:deb/ubuntu/libarchive@3.8.5-1ubuntu2.2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.8.5-1ubuntu2.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.7.7-0ubuntu3",
        "3.8.5-1ubuntu1",
        "3.8.5-1ubuntu2",
        "3.8.5-1ubuntu2.1"
      ]
    }
  ],
  "aliases": [],
  "details": "A flaw was found in libarchive. A NULL pointer dereference vulnerability exists in the ACL parsing logic, specifically within the archive_acl_from_text_nl() function. When processing a malformed ACL string (such as a bare \"d\" or \"default\" tag without subsequent fields), the function fails to perform adequate validation before advancing the pointer. An attacker can exploit this by providing a maliciously crafted archive, causing an application utilizing the libarchive API (such as bsdtar) to crash, resulting in a Denial of Service (DoS).",
  "id": "UBUNTU-CVE-2026-5745",
  "modified": "2026-07-22T23:16:25Z",
  "published": "2026-04-07T16:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-5745"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-5745"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-5745"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8581-1"
    }
  ],
  "related": [
    "USN-8581-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-5745"
  ]
}



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