CVE-2026-5172

Severity CVSS v4.0:

Pending analysis

Type:

CWE-125 Out-of-bounds Read

Publication date:

11/05/2026

Last modified:

30/06/2026

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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L CVSS v3.1 Severity and Metrics:

Base Score: 7.30 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): Low
Availability (A): Low

Base Score 3.x

7.30

Severity 3.x

HIGH

References to Advisories, Solutions, and Tools

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