UBUNTU-CVE-2026-12969 (CVE-2026-12969)

Vulnerability from osv_ubuntu – Published: 2026-06-23 14:17 – Updated: 2026-07-14 21:35 – Source website
VLAI
Details

An out-of-bounds read vulnerability exists in dnsmasq's find_soa() function in src/rfc1035.c. When parsing NS section records, extract_name() is called with extrabytes=0, failing to validate that 10 additional bytes exist for fixed-length DNS record fields. A remote attacker controlling a DNS zone can exploit this via a crafted NXDOMAIN response to cause a 10-byte heap out-of-bounds read, potentially accessing stale data from prior transactions.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "dnsmasq",
            "binary_version": "2.90-0ubuntu0.16.04.1+esm4"
          },
          {
            "binary_name": "dnsmasq-base",
            "binary_version": "2.90-0ubuntu0.16.04.1+esm4"
          },
          {
            "binary_name": "dnsmasq-base-lua",
            "binary_version": "2.90-0ubuntu0.16.04.1+esm4"
          },
          {
            "binary_name": "dnsmasq-utils",
            "binary_version": "2.90-0ubuntu0.16.04.1+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "dnsmasq",
        "purl": "pkg:deb/ubuntu/dnsmasq@2.90-0ubuntu0.16.04.1+esm4?arch=source\u0026distro=esm-infra-legacy/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.90-0ubuntu0.16.04.1+esm4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.75-1",
        "2.75-1ubuntu0.16.04.1",
        "2.75-1ubuntu0.16.04.2",
        "2.75-1ubuntu0.16.04.3",
        "2.75-1ubuntu0.16.04.4",
        "2.75-1ubuntu0.16.04.5",
        "2.75-1ubuntu0.16.04.7",
        "2.75-1ubuntu0.16.04.8",
        "2.75-1ubuntu0.16.04.10",
        "2.75-1ubuntu0.16.04.10+esm1",
        "2.79-1ubuntu0.16.04.1+esm1",
        "2.79-1ubuntu0.16.04.1+esm2",
        "2.90-0ubuntu0.16.04.1+esm1",
        "2.90-0ubuntu0.16.04.1+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "dnsmasq",
            "binary_version": "2.90-0ubuntu0.18.04.1+esm4"
          },
          {
            "binary_name": "dnsmasq-base",
            "binary_version": "2.90-0ubuntu0.18.04.1+esm4"
          },
          {
            "binary_name": "dnsmasq-base-lua",
            "binary_version": "2.90-0ubuntu0.18.04.1+esm4"
          },
          {
            "binary_name": "dnsmasq-utils",
            "binary_version": "2.90-0ubuntu0.18.04.1+esm4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "dnsmasq",
        "purl": "pkg:deb/ubuntu/dnsmasq@2.90-0ubuntu0.18.04.1+esm4?arch=source\u0026distro=esm-infra/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.90-0ubuntu0.18.04.1+esm4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.78-1",
        "2.78-3",
        "2.79-1",
        "2.79-1ubuntu0.2",
        "2.79-1ubuntu0.3",
        "2.79-1ubuntu0.4",
        "2.79-1ubuntu0.5",
        "2.79-1ubuntu0.6",
        "2.79-1ubuntu0.7",
        "2.90-0ubuntu0.18.04.1+esm1",
        "2.90-0ubuntu0.18.04.1+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro",
        "binaries": [
          {
            "binary_name": "dnsmasq",
            "binary_version": "2.90-0ubuntu0.20.04.1+esm3"
          },
          {
            "binary_name": "dnsmasq-base",
            "binary_version": "2.90-0ubuntu0.20.04.1+esm3"
          },
          {
            "binary_name": "dnsmasq-base-lua",
            "binary_version": "2.90-0ubuntu0.20.04.1+esm3"
          },
          {
            "binary_name": "dnsmasq-utils",
            "binary_version": "2.90-0ubuntu0.20.04.1+esm3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "dnsmasq",
        "purl": "pkg:deb/ubuntu/dnsmasq@2.90-0ubuntu0.20.04.1+esm3?arch=source\u0026distro=esm-infra/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.90-0ubuntu0.20.04.1+esm3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.80-1ubuntu2",
        "2.80-1ubuntu4",
        "2.80-1.1ubuntu1",
        "2.80-1.1ubuntu1.2",
        "2.80-1.1ubuntu1.3",
        "2.80-1.1ubuntu1.4",
        "2.80-1.1ubuntu1.5",
        "2.80-1.1ubuntu1.6",
        "2.80-1.1ubuntu1.7",
        "2.90-0ubuntu0.20.04.1",
        "2.90-0ubuntu0.20.04.1+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dnsmasq",
            "binary_version": "2.90-0ubuntu0.22.04.4"
          },
          {
            "binary_name": "dnsmasq-base",
            "binary_version": "2.90-0ubuntu0.22.04.4"
          },
          {
            "binary_name": "dnsmasq-base-lua",
            "binary_version": "2.90-0ubuntu0.22.04.4"
          },
          {
            "binary_name": "dnsmasq-utils",
            "binary_version": "2.90-0ubuntu0.22.04.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "dnsmasq",
        "purl": "pkg:deb/ubuntu/dnsmasq@2.90-0ubuntu0.22.04.4?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.90-0ubuntu0.22.04.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.85-1ubuntu2",
        "2.86-1.1",
        "2.86-1.1ubuntu0.1",
        "2.86-1.1ubuntu0.2",
        "2.86-1.1ubuntu0.3",
        "2.86-1.1ubuntu0.4",
        "2.86-1.1ubuntu0.5",
        "2.90-0ubuntu0.22.04.1",
        "2.90-0ubuntu0.22.04.3"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dnsmasq",
            "binary_version": "2.90-2ubuntu0.4"
          },
          {
            "binary_name": "dnsmasq-base",
            "binary_version": "2.90-2ubuntu0.4"
          },
          {
            "binary_name": "dnsmasq-base-lua",
            "binary_version": "2.90-2ubuntu0.4"
          },
          {
            "binary_name": "dnsmasq-utils",
            "binary_version": "2.90-2ubuntu0.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "dnsmasq",
        "purl": "pkg:deb/ubuntu/dnsmasq@2.90-2ubuntu0.4?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.90-2ubuntu0.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.89-1",
        "2.90-2",
        "2.90-2build1",
        "2.90-2build2",
        "2.90-2ubuntu0.1",
        "2.90-2ubuntu0.3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "dnsmasq",
            "binary_version": "2.91-1ubuntu0.2"
          },
          {
            "binary_name": "dnsmasq-base",
            "binary_version": "2.91-1ubuntu0.2"
          },
          {
            "binary_name": "dnsmasq-base-lua",
            "binary_version": "2.91-1ubuntu0.2"
          },
          {
            "binary_name": "dnsmasq-utils",
            "binary_version": "2.91-1ubuntu0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "dnsmasq",
        "purl": "pkg:deb/ubuntu/dnsmasq@2.91-1ubuntu0.2?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.91-1",
        "2.91-1build1",
        "2.91-1ubuntu0.2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "dnsmasq",
            "binary_version": "2.92-1ubuntu0.4"
          },
          {
            "binary_name": "dnsmasq-base",
            "binary_version": "2.92-1ubuntu0.4"
          },
          {
            "binary_name": "dnsmasq-base-lua",
            "binary_version": "2.92-1ubuntu0.4"
          },
          {
            "binary_name": "dnsmasq-utils",
            "binary_version": "2.92-1ubuntu0.4"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "dnsmasq",
        "purl": "pkg:deb/ubuntu/dnsmasq@2.92-1ubuntu0.4?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.92-1ubuntu0.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.91-1build1",
        "2.92~rc3-1",
        "2.92-1",
        "2.92-1ubuntu0.2",
        "2.92-1ubuntu0.3"
      ]
    }
  ],
  "aliases": [],
  "details": "An out-of-bounds read vulnerability exists in dnsmasq\u0027s find_soa() function in src/rfc1035.c. When parsing NS section records, extract_name() is called with extrabytes=0, failing to validate that 10 additional bytes exist for fixed-length DNS record fields. A remote attacker controlling a DNS zone can exploit this via a crafted NXDOMAIN response to cause a 10-byte heap out-of-bounds read, potentially accessing stale data from prior transactions.",
  "id": "UBUNTU-CVE-2026-12969",
  "modified": "2026-07-14T21:35:57Z",
  "published": "2026-06-23T14:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-12969"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-12969"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8542-1"
    }
  ],
  "related": [
    "USN-8542-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-12969"
  ]
}



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