CVE-2026-5172
Medium
Elevated severity or exploit probability.
CVSS base
7.3
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
EPSS — probability of exploitation (30 days)
0.7%
50.6th percentile
CISA KEV
Not listed
Weakness / dates
CWE-125
Published 2026-05-11 · modified 2026-08-24
Description
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.
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