Heap-based Out-of-Bounds Write in dnsmasq DHCPv6

Publication date: 2026-05-11

Last updated on: 2026-07-02

Assigner: CERT/CC

Description

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.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-05-11

Last Modified

2026-07-02

Generated

2026-07-11

AI Q&A

2026-05-11

EPSS Evaluated

2026-07-10

NVD

CVE-2026-4892

EUVD

EUVD-2026-29154

Affected Vendors & Products

Vendor	Product	Version / Range
the_knot	dhcpv6	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-122	A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc().

Attack-Flow Graph

Executive Summary

This vulnerability is a heap-based out-of-bounds write in the DHCPv6 implementation of dnsmasq. It allows local attackers to execute arbitrary code with root privileges by sending a specially crafted DHCPv6 packet.

Impact Analysis

An attacker exploiting this vulnerability can gain root privileges on the affected system, allowing them to execute arbitrary code. This can lead to full system compromise, unauthorized access, data theft, or disruption of services.

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