Skip to content
Heist/ feed
UnratedFix available

DEBIAN-CVE-2026-4891

Type: advisorySource: OSV1 source record

A heap-based out-of-bounds read vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a crafted DNS packet.

Announced Source revision 1
Original source ↗

DEBIAN-CVE-2026-4891

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:DEBIAN-CVE-2026-4891

dnsmasq

Source reference: /affected/0/package/name

Affected versions
2.89-1

Source reference: /affected/0/versions

2.90-1

Source reference: /affected/0/versions

2.90-2

Source reference: /affected/0/versions

2.90-3

Source reference: /affected/0/versions

2.90-4~deb12u1

Source reference: /affected/0/versions

Fixed versions
2.90-4~deb12u2

Source reference: /affected/0/ranges

Prerequisites
Not stated in this record

dnsmasq

Source reference: /affected/1/package/name

Affected versions
2.91-1

Source reference: /affected/1/versions

Fixed versions
2.91-1+deb13u1

Source reference: /affected/1/ranges

Prerequisites
Not stated in this record

dnsmasq

Source reference: /affected/2/package/name

Affected versions
2.91-1

Source reference: /affected/2/versions

2.92-1

Source reference: /affected/2/versions

2.92-1+exp1

Source reference: /affected/2/versions

2.92-1~exp1

Source reference: /affected/2/versions

2.92-2

Source reference: /affected/2/versions

2.92-3

Source reference: /affected/2/versions

2.92-4

Source reference: /affected/2/versions

2.92~rc1-1

Source reference: /affected/2/versions

2.92~rc3-1

Source reference: /affected/2/versions

Fixed versions
2.92-5

Source reference: /affected/2/ranges

Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "2.90-4~deb12u2"
          }
        ]
      }
    ],
    "package": {
      "name": "dnsmasq",
      "purl": "pkg:deb/debian/dnsmasq?arch=source&distro=bookworm",
      "ecosystem": "Debian:12"
    },
    "versions": [
      "2.89-1",
      "2.90-1",
      "2.90-2",
      "2.90-3",
      "2.90-4~deb12u1"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4891.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "2.91-1+deb13u1"
          }
        ]
      }
    ],
    "package": {
      "name": "dnsmasq",
      "purl": "pkg:deb/debian/dnsmasq?arch=source&distro=trixie",
      "ecosystem": "Debian:13"
    },
    "versions": [
      "2.91-1"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4891.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0"
          },
          {
            "fixed": "2.92-5"
          }
        ]
      }
    ],
    "package": {
      "name": "dnsmasq",
      "purl": "pkg:deb/debian/dnsmasq?arch=source&distro=forky",
      "ecosystem": "Debian:14"
    },
    "versions": [
      "2.91-1",
      "2.92-1",
      "2.92-1+exp1",
      "2.92-1~exp1",
      "2.92-2",
      "2.92-3",
      "2.92-4",
      "2.92~rc1-1",
      "2.92~rc3-1"
    ],
    "database_specific": {
      "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-4891.json"
    },
    "ecosystem_specific": {
      "urgency": "not yet assigned"
    }
  }
]

Publisher severity

No explicit severity was provided.

Event
#56575 · Revision 1
Added to Heist Feed
Publisher date
Read the original announcement