CVE-2026-5172

EUVD-2026-29156
A buffer overflow in dnsmasq’s extract_addresses() function allows an attacker to trigger a heap out-of-bounds read and crash by exploiting a malformed DNS response, enabling extract_name() to advance the pointer past the record’s end.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.3 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: 84.41%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
Red HatRed Hat Enterprise Linux 10
0:2.90-7.el10_2 ≤
𝑥
< *
ADP
Debian logo
Debian Releases
Debian Product
Codename
dnsmasq
bookworm
2.90-4~deb12u2
fixed
bookworm (security)
2.90-4~deb12u2
fixed
bullseye
2.85-1
fixed
bullseye (security)
2.85-1+deb11u2
fixed
forky
2.93-1
fixed
sid
2.93-1
fixed
trixie
2.91-1+deb13u1
fixed
trixie (security)
2.91-1+deb13u1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
dnsmasq
bionic
Fixed 2.90-0ubuntu0.18.04.1+esm3
released
focal
Fixed 2.90-0ubuntu0.20.04.1+esm2
released
jammy
Fixed 2.90-0ubuntu0.22.04.3
released
noble
Fixed 2.90-2ubuntu0.3
released
questing
Fixed 2.91-1ubuntu0.2
released
resolute
Fixed 2.92-1ubuntu0.2
released
trusty
not-affected
xenial
Fixed 2.90-0ubuntu0.16.04.1+esm3
released
Amazon Linux logo
Amazon Linux Releases
Amazon Package
Release
dnsmasq
Amazon Linux 2023
0:2.90-1.amzn2023.0.3
fixed
dnsmasq-debuginfo
Amazon Linux 2023
0:2.90-1.amzn2023.0.3
fixed
dnsmasq-debugsource
Amazon Linux 2023
0:2.90-1.amzn2023.0.3
fixed
dnsmasq-utils
Amazon Linux 2023
0:2.90-1.amzn2023.0.3
fixed
dnsmasq-utils-debuginfo
Amazon Linux 2023
0:2.90-1.amzn2023.0.3
fixed
Azure Linux logo
Azure Linux Releases
Azure Package
Release
dnsmasq
Azure Linux 3.0
0:2.92-1.azl3
fixed
Common Weakness Enumeration
References
https://github.com/NixOS/nixpkgs/pull/519082
https://github.com/NixOS/nixpkgs/pull/519093
https://github.com/pi-hole/FTL/releases/tag/v6.6.2
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2026q2/018471.html
https://thekelleys.org.uk/dnsmasq/CVE/
https://www.kb.cert.org/vuls/id/471747
https://access.redhat.com/errata/RHSA-2026:19158
https://access.redhat.com/security/cve/CVE-2026-5172
https://bugzilla.redhat.com/show_bug.cgi?id=2458521
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5172.json