CVE-2026-41292

Description

NLnet Labs Unbound up to and including version 1.25.0 is vulnerable to a degradation of service attack related to parsing long lists of incoming EDNS options. An adversary sending queries with too many EDNS options can hold Unbound threads hostage while they are parsing and creating internal data structures for the options. Coordinated attacks can result in degradation and/or denial of service. Unbound 1.25.1 contains a patch with a fix to limit acceptable incoming EDNS options (100).

Overview

State: PUBLISHED
Assigner (CNA): NLnet Labs
CVSS severity: MEDIUM
CVSS score: 6.6 / 10
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Red
Effective score: 6.6 / 10 MEDIUM source: CNA overview
MSRC score: 7.5 / 10 HIGH MS rating: Moderate
CWE(s): CWE-407, CWE-770
Reserved: 2026-05-07
Published: 2026-05-20 09:19 UTC
Last updated: 2026-05-20 12:11 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/41xxx/CVE-2026-41292.json
Linked Threat: CVE-2026-41292 — CVE-2026-41292

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: 2026-05-20 10:16:27 UTC
NVD last modified: 2026-05-20 22:49:46 UTC
NVD CVSS v3.1: 7.5 / 10 HIGH source: nvd@nist.gov
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploitability subscore: 3.9 / 10
Impact subscore: 3.6 / 10
EPSS score: 0.0006 (probability of exploitation in next 30 days)
EPSS percentile: 17.85% 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-2026-31078
Assigner: NLnet Labs
Published: May 20, 2026, 9:19:13 AM
Updated: May 20, 2026, 12:11:23 PM
EUVD base score (CVSS 4.0): 6.6 / 10
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Red
EUVD-reported EPSS: 0.0800
Vendors: NLnet Labs
Products: Unbound (0 <1.25.1)
Aliases: GHSA-2wvj-gvc7-gfhx

ENISA description: NLnet Labs Unbound up to and including version 1.25.0 is vulnerable to a degradation of service attack related to parsing long lists of incoming EDNS options. An adversary sending queries with too many EDNS options can hold Unbound threads hostage while they are parsing and creating internal data structures for the options. Coordinated attacks can result in degradation and/or denial of service. Unbound 1.25.1 contains a patch with a fix to limit acceptable incoming EDNS options (100).

EUVD references (1)

https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt

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 2026-07-28 03:00 UTC (source: CVRF).

MS severity: Moderate
MS CVSS base score: 7.5 / 10 (temporal 7.5)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Release: 2026-May

Microsoft remediations / KB articles (2)

CBL-Mariner Releases — Vendor Fix / Security Update (fixed build 1.25.1-1)
https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / CBL-Mariner Releases

Affected products (1)

Vendor	Product	Versions	Platforms
NLnet Labs	Unbound	`0` (affected)	—

Affected products — CPE 2.3 (1) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:*

Vendor references (1)

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

https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt vendor-advisory

Web references (6)

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

None Available msrc
MSRC update guide: CVE-2026-41292 msrc
https://nvd.nist.gov/vuln/detail/CVE-2026-41292 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-41292 tenable:www.cve.org
https://www.first.org/epss/ tenable:www.first.org
https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt tenable:www.nlnetlabs.nl

NVD-tagged references (1)

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://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt sep@nlnetlabs.nl MitigationVendor Advisory

Remediations (17)

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

CVE-2026-41292 - Vulnerability Details - OpenCVE

web:app.opencve.io

An adversary sending queries with too many EDNS options can hold Unbound threads hostage while they are parsing and creating internal data structures for the options. Coordinated attacks can result in degradation and/ or denial of service. Unbound 1.25.1 contains a patch with a fix to limit acceptable incoming EDNS options (100).

2026-05-23 22:16 UTC
Critical Chrome Vulnerabilities Enables Remote Code Execution Attacks ...

web:cybersecuritynews.com

Google released a critical Chrome update fixing multiple high-risk vulnerabilities that could enable arbitrary code execution.

2026-05-23 22:16 UTC
CVE-2026-41292 | Security Details | Sonatype Guide

web:guide.sonatype.com

Technical security analysis for CVE-2026-41292 . CVSS 7.5 severity. View CVSS vectors, CWE classifications, and exploit maturity ratings.

2026-05-23 22:16 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 22:16 UTC
NVD - cve-2026-41292

web:nvd.nist.gov

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

2026-05-23 22:16 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 22:16 UTC
Cyber Threats and Response - CISA

web:www.cisa.gov

Sophisticated cyber actors and nation-states exploit vulnerabilities to steal information and money and work to develop capabilities to disrupt, destroy, or threaten the delivery of essential services. Defending against these attacks is essential to maintaining the nation's security. Any cyber-attack, no matter how small, is a threat to our national security and must be identified, managed ...

2026-05-23 22:16 UTC
CVE: Common Vulnerabilities and Exposures

web:www.cve.org

At cve .org, we provide the authoritative reference method for publicly known information-security vulnerabilities and exposures

2026-05-23 22:16 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 22:16 UTC
Microsoft fixes 167 security flaws in April, second biggest Patch ...

web:www.pcworld.com

This month's Patch Tuesday includes an actively exploited Office zero-day vulnerability and several critical RCE bugs in Windows and Remote Desktop.

2026-05-23 22:16 UTC
Google publishes exploit code threatening millions of Chromium ...

web:arstechnica.com

Google publishes exploit code threatening millions of Chromium users Google publishes exploit code before patch , reported 42 months earlier, is fixed.

2026-05-26 02:59 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 02:59 UTC
Unbound <1.25.1 DoS via Excess EDNS Options: CVE-2026-41292 May 2026

web:stack.watch

An adversary sending queries with too many EDNS options can hold Unbound threads hostage while they are parsing and creating internal data structures for the options. Coordinated attacks can result in degradation and/ or denial of service. Unbound 1.25.1 contains a patch with a fix to limit acceptable incoming EDNS options (100). Vendor Advisory NVD

2026-05-26 02:59 UTC
Critical Patches Issued for Microsoft Products, May 12, 2026

web:www.cisecurity.org

<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...

2026-05-26 02:59 UTC
Microsoft Technical Security Notifications

web:www.microsoft.com

Security Update Guide Notifications Microsoft's free Security Update Guide Notifications provide links to security-related software updates and notification of re-released security updates. These notifications are sent via email throughout the month as needed.

2026-05-26 02:59 UTC
CVE-2026-41292 | Tenable®

web:www.tenable.com

An adversary sending queries with too many EDNS options can hold Unbound threads hostage while they are parsing and creating internal data structures for the options. Coordinated attacks can result in degradation and/ or denial of service. Unbound 1.25.1 contains a patch with a fix to limit acceptable incoming EDNS options (100).

2026-05-26 02:59 UTC
CVE-2026-41292 - High Vulnerability - TheHackerWire

web:www.thehackerwire.com

How do I fix or mitigate CVE-2026-41292 ? To protect against CVE-2026-41292 , you should: (1) Apply the latest security patches from Nlnetlabs, (2) Check official security advisories for specific remediation steps, (3) Update affected software to the latest version, and (4) Monitor your systems for any signs of exploitation.

2026-05-26 02:59 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-41292.json.

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