CVE-2026-4892

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.

Overview

State: PUBLISHED
Assigner (CNA): certcc
CVSS severity: high
CVSS score: 8.4 / 10
CVSS vector: AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Effective score: 8.4 / 10 HIGH source: CNA overview
MSRC score: 8.4 / 10 HIGH MS rating: Important
CWE(s): CWE-122: Heap-based Buffer Overflow
Reserved: 2026-03-26
Published: 2026-05-11 18:47 UTC
Last updated: 2026-05-11 21:58 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/4xxx/CVE-2026-4892.json
Linked Threat: CVE-2026-4892 — CVE-2026-4892

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-05-11 18:16:41 UTC
NVD last modified: 2026-05-12 14:15:46 UTC
NVD CVSS v3.1: 8.4 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploitability subscore: 2.5 / 10
Impact subscore: 5.9 / 10
EPSS score: 0.0001 (probability of exploitation in next 30 days)
EPSS percentile: 2.30% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-29154
Assigner: certcc
Published: May 11, 2026, 4:47:58 PM
Updated: May 20, 2026, 2:09:29 PM
EUVD base score (CVSS 3.1): 8.4 / 10
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EUVD-reported EPSS: 0.0100
Vendors: dnsmasq
Products: dnsmasq (2.92rel2)

dnsmasq (2.93)

dnsmasq (0 <2.92rel2)

ENISA 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.

EUVD references (6)

Microsoft Security Response Center MSRC

Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-08-11 02:04 UTC (source: CVRF).

MS severity: Important
MS CVSS base score: 8.4 / 10 (temporal 7.7)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U
Release: 2026-May

Affected products (1)

Vendor	Product	Versions	Platforms
dnsmasq	dnsmasq	`2.92rel2` (affected)	—

Vendor references (6)

References embedded in the original CVE record by the assigning CNA.

MITRE references (6) cveawg.mitre.org

Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.

Web references (8)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

MSRC update guide: CVE-2026-4892 msrc
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-29154 rapid7:euvd.enisa.europa.eu
https://attackerkb.com/topics/CVE-2026-4892 rapid7:attackerkb.com
https://security.alpinelinux.org/vuln/CVE-2026-4892 rapid7:security.alpinelinux.org
https://nvd.nist.gov/vuln/detail/CVE-2026-4892 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-4892 tenable:www.cve.org
https://www.first.org/epss/ tenable:www.first.org
https://kb.cert.org/vuls/id/471747 tenable:kb.cert.org

NVD-tagged references (6)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/NixOS/nixpkgs/pull/519082 cret@cert.org
https://github.com/NixOS/nixpkgs/pull/519093 cret@cert.org
https://github.com/pi-hole/FTL/releases/tag/v6.6.2 cret@cert.org
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2026q2/018471.html cret@cert.org
https://thekelleys.org.uk/dnsmasq/CVE/ cret@cert.org
https://www.kb.cert.org/vuls/id/471747 cret@cert.org

Remediations (17)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

CVE-2026-4892 - Vulnerability Details - OpenCVE

web:app.opencve.io

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.

2026-05-23 21:01 UTC
Microsoft and Adobe Patch Tuesday, April 2026 Security Update Review

web:blog.qualys.com

With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.

2026-05-23 21:01 UTC
April 2026 Critical Patch Update Released | security - Oracle Blogs

web:blogs.oracle.com

For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.

2026-05-23 21:01 UTC
Patch Tuesday, May 2026 Edition - Krebs on Security

web:krebsonsecurity.com

Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.

2026-05-23 21:01 UTC
Nvd - Cve-2026-4892

web:nvd.nist.gov

An official website of the United States government Here's how you know

2026-05-23 21:01 UTC
Security Update Guide - Microsoft

web:portal.msrc.microsoft.com

The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.

2026-05-23 21:01 UTC
Microsoft Issues Second Biggest Patch Tuesday Ever in April

web:redmondmag.com

Microsoft April 2026 Patch Tuesday fixed 163 CVEs , marking its second-largest security update. Three zero-day vulnerabilities impacted SharePoint, Chromium-based Edge workflows and Microsoft Defender.

2026-05-23 21:01 UTC
Landing Page | ServiceNow Common Vulnerabilities & Exposures (CVE ...

web:support.servicenow.com

Overview The advisories below document publicly disclosed Common Vulnerabilities and Exposures ( CVEs ) in the Now Platform by ServiceNow. Because ServiceNow uses various methods to communicate vulnerability information, patches, and other fixes, customers should review family, security patch , and hotfix release notes, which are available at https://docs.servicenow.com, for a complete list of ...

2026-05-23 21:01 UTC
Microsoft March 2026 Patch Tuesday fixes 2 zero-days, 79 flaws

web:www.bleepingcomputer.com

Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.

2026-05-23 21:01 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-05-23 21:01 UTC
Windows Kerberos RC4 deprecation: what will break in Active ... - 4sysops

web:4sysops.com

Starting in April 2026 , Windows updates will change the default Kerberos ticket issuance behavior to AES-SHA1 for accounts without explicit encryption settings, while RC4 can still be used where explicitly enabled. This change, driven by CVE - 2026 -20833, affects every Windows Server environment where service accounts or devices still rely on RC4. Any service account, NAS device, or legacy ...

2026-05-26 02:50 UTC
CVE-2026-4892 - CVE-2026-4892 - cvefeed.io

web:cvefeed.io

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.

2026-05-26 02:50 UTC
CISA Warns of Exploited Microsoft Defender 0-Day Flaws

web:cyberpress.org

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .

2026-05-26 02:50 UTC
N-central third-party software patch list

web:documentation.n-able.com

For more information on how Patch Manager provides third-party patching, see Patching third-party software. Use the table's InstallerURLs location when configuring vendor and patch exclusions in your firewalls and other web-monitoring software.

2026-05-26 02:50 UTC
January 24, 2026—KB5078127 (OS Builds 26200.7628 and 26100.7628) Out-of ...

web:support.microsoft.com

It includes updates from previous security and non-security releases, along with an additional fix . To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained.

2026-05-26 02:50 UTC
Emergency patch issued for Microsoft Office, 365 over hacking threat - MSN

web:www.msn.com

Original story: Microsoft has released an emergency patch for a vulnerability in the company's Office programs that's already being exploited by hackers.

2026-05-26 02:50 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-26 02:50 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-4892.json.

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              "baseScore": 8.4,
              "baseSeverity": "HIGH",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
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                  }
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                "version": "2.0.3"
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        },
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