CVE-2026-4893
Received Received - Intake
Information Disclosure in Dnsmasq via RFC 7871 Bypass

Publication date: 2026-05-11

Last updated on: 2026-05-11

Assigner: CERT/CC

Description
An information disclosure vulnerability in dnsmasq allows remote attackers to bypass source checks via a crafted DNS packet with RFC 7871 client subnet information.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-05-11
Last Modified
2026-05-11
Generated
2026-06-21
AI Q&A
2026-05-11
EPSS Evaluated
2026-06-19
NVD
CVE-2026-4893
EUVD
EUVD-2026-29155
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
the_dnsmasq_project dnsmasq *
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability is an information disclosure issue in dnsmasq. It allows remote attackers to bypass source checks by sending a specially crafted DNS packet that includes RFC 7871 client subnet information.

Impact Analysis

The vulnerability can lead to unauthorized information disclosure because attackers can bypass source checks. This may allow them to gain access to information that should be restricted, potentially compromising network security.

Compliance Impact

The provided context and resources do not contain information regarding the impact of CVE-2026-4893 on compliance with common standards and regulations such as GDPR or HIPAA.

Mitigation Strategies

To mitigate the information disclosure vulnerability in dnsmasq (CVE-2026-4893), you should update dnsmasq to the patched version 2.92rel2 or later, which includes fixes for this and related vulnerabilities.

The patched version 2.92rel2 is available on the official dnsmasq website and has been incorporated into various package repositories, including NixOS.

Testing the updated version in your environment before full deployment is recommended to ensure stability.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-4893. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart