CVE catalog
CVE-2026-4892
A heap-based out-of-bounds write vulnerability in the…
A heap-based out-of-bounds write vulnerability in the DHCPv6 implementation of dnsmasq allows local attackers to execute arbitrary code with root privileges via a crafted DHCPv6 packet.
- Severity
- High · CVSS 8.8
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.81% · Oct 27, 2026
Projects and upstream resources
Reported versions and fixes
Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.
Version impact has not been established. The original provider fields are retained below.
Provider details and historical evidence
Original provider fields
{
"package_releases": [
{
"name": "dnsmasq",
"status": "fixed",
"release": "sid",
"version": "2.93-3"
},
{
"name": "dnsmasq",
"status": "fixed",
"release": "forky",
"version": "2.93-3"
},
{
"name": "dnsmasq",
"status": "fixed",
"release": "trixie",
"version": "2.91-1+deb13u2"
},
{
"name": "dnsmasq",
"status": "fixed",
"release": "trixie-security",
"version": "2.91-1+deb13u1"
},
{
"name": "dnsmasq",
"status": "fixed",
"release": "bookworm",
"version": "2.90-4~deb12u2"
},
{
"name": "dnsmasq",
"status": "fixed",
"release": "bookworm-security",
"version": "2.90-4~deb12u2"
}
],
"fixed_versions": [
{
"bug": null,
"name": "dnsmasq",
"type": "source",
"origin": null,
"release": "sid",
"urgency": "not yet assigned",
"fixed_version": "2.92-5"
},
{
"bug": null,
"name": "dnsmasq",
"type": "source",
"origin": null,
"release": "forky",
"urgency": "not yet assigned",
"fixed_version": "2.92-5"
},
{
"bug": null,
"name": "dnsmasq",
"type": "source",
"origin": null,
"release": "trixie",
"urgency": "not yet assigned",
"fixed_version": "2.91-1+deb13u1"
},
{
"bug": null,
"name": "dnsmasq",
"type": "source",
"origin": null,
"release": "bookworm",
"urgency": "not yet assigned",
"fixed_version": "2.90-4~deb12u2"
}
],
"distribution_packages": [
{
"name": "dnsmasq",
"ecosystem": "cpe",
"fixed_version": "2.90-2ubuntu0.3"
},
{
"name": "dnsmasq-base",
"ecosystem": "cpe",
"fixed_version": "2.90-2ubuntu0.3"
},
{
"name": "dnsmasq-base-lua",
"ecosystem": "cpe",
"fixed_version": "2.90-2ubuntu0.3"
},
{
"name": "dnsmasq-utils",
"ecosystem": "cpe",
"fixed_version": "2.90-2ubuntu0.3"
},
{
"name": "dnsmasq",
"ecosystem": "cpe",
"fixed_version": "2.90-4~deb12u2"
},
{
"name": "dnsmasq",
"distro": "alpine",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.91-r1"
}
]
}
],
"release": "3.22",
"versions": [],
"ecosystem": "apk",
"fixed_version": "2.91-r1",
"provider_record_id": "ALPINE-CVE-2026-4892"
},
{
"name": "dnsmasq",
"distro": "alpine",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.91-r1"
}
]
}
],
"release": "3.23",
"versions": [],
"ecosystem": "apk",
"fixed_version": "2.91-r1",
"provider_record_id": "ALPINE-CVE-2026-4892"
},
{
"name": "dnsmasq",
"distro": "alpine",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.92_p2-r0"
}
]
}
],
"release": "3.24",
"versions": [],
"ecosystem": "apk",
"fixed_version": "2.92_p2-r0",
"provider_record_id": "ALPINE-CVE-2026-4892"
},
{
"name": "dnsmasq",
"distro": "ubuntu",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.90-0ubuntu0.20.04.1+esm2"
}
]
}
],
"release": "pro",
"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"
],
"ecosystem": "deb",
"fixed_version": "2.90-0ubuntu0.20.04.1+esm2",
"provider_record_id": "UBUNTU-CVE-2026-4892"
},
{
"name": "dnsmasq",
"distro": "ubuntu",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.90-0ubuntu0.22.04.3"
}
]
}
],
"release": "22.04",
"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"
],
"ecosystem": "deb",
"fixed_version": "2.90-0ubuntu0.22.04.3",
"provider_record_id": "UBUNTU-CVE-2026-4892"
},
{
"name": "dnsmasq",
"distro": "ubuntu",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.90-2ubuntu0.3"
}
]
}
],
"release": "24.04",
"versions": [
"2.89-1",
"2.90-2",
"2.90-2build1",
"2.90-2build2",
"2.90-2ubuntu0.1"
],
"ecosystem": "deb",
"fixed_version": "2.90-2ubuntu0.3",
"provider_record_id": "UBUNTU-CVE-2026-4892"
},
{
"name": "dnsmasq",
"distro": "ubuntu",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.91-1ubuntu0.2"
}
]
}
],
"release": "25.10",
"versions": [
"2.91-1",
"2.91-1build1"
],
"ecosystem": "deb",
"fixed_version": "2.91-1ubuntu0.2",
"provider_record_id": "UBUNTU-CVE-2026-4892"
},
{
"name": "dnsmasq",
"distro": "ubuntu",
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "2.92-1ubuntu0.2"
}
]
}
],
"release": "26.04",
"versions": [
"2.91-1build1",
"2.92~rc3-1",
"2.92-1"
],
"ecosystem": "deb",
"fixed_version": "2.92-1ubuntu0.2",
"provider_record_id": "UBUNTU-CVE-2026-4892"
}
]
}OpenFactory catalog packages
Matching against OpenFactory catalog package versions is in progress.
[Debian 12 (Bookworm)]
- [dnsmasq]Unknown
Details (4)
2.90-4~deb12u2· all · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· all · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· all · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· all · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
- [dnsmasq-base]Unknown
Source package: [dnsmasq]
Details (4)
2.90-4~deb12u2· amd64 · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· arm64 · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· amd64 · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· arm64 · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
- [dnsmasq-base-lua]Unknown
Source package: [dnsmasq]
Details (4)
2.90-4~deb12u2· amd64 · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· arm64 · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· amd64 · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· arm64 · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
- [dnsmasq-utils]Unknown
Source package: [dnsmasq]
Details (4)
2.90-4~deb12u2· amd64 · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· arm64 · bookwormFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· amd64 · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
2.90-4~deb12u2· arm64 · bookworm-securityFixed · Fixed:
2.90-4~deb12u2nvd · dnsmasq · debian · bookworm; nvd · dnsmasq · debian · 12
[Debian 13 (Trixie)]
- [dnsmasq]Unknown
Details (4)
2.91-1+deb13u1· all · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· all · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· all · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· all · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
- [dnsmasq-base]Unknown
Source package: [dnsmasq]
Details (4)
2.91-1+deb13u1· amd64 · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· arm64 · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· amd64 · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· arm64 · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
- [dnsmasq-base-lua]Unknown
Source package: [dnsmasq]
Details (4)
2.91-1+deb13u1· amd64 · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· arm64 · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· amd64 · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· arm64 · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
- [dnsmasq-utils]Unknown
Source package: [dnsmasq]
Details (4)
2.91-1+deb13u1· amd64 · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· arm64 · trixieFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· amd64 · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
2.91-1+deb13u1· arm64 · trixie-securityFixed · Fixed:
2.91-1+deb13u1nvd · dnsmasq · debian · 13
Observed:
References
- [https://access.redhat.com/errata/RHSA-2026:40762]
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2026_20748-1.json]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-4892]
- [https://osv.dev/vulnerability/ALPINE-CVE-2026-4892]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-4892]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-4892]
- [https://security-tracker.debian.org/tracker/CVE-2026-4892]
- [https://ubuntu.com/security/notices/USN-8268-1]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-1468.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX] · [Ubuntu Security Notices (USN)]