---
id: CVE-2026-41292
title: >-
  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
summary: >-
  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 threa…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-407
  - CWE-770
  - CWE-1050
vendor: nlnetlabs
product: unbound
affected:
  - unbound < 1.25.1
patched:
  - unbound 1.25.1
published: '2026-05-20'
updated: '2026-07-16'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-41292'
references:
  - url: 'https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-41292.txt'
    label: sep@nlnetlabs.nl
  - url: 'https://access.redhat.com/errata/RHSA-2026:24013'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/security/cve/CVE-2026-41292'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2480125'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-41292.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
epss: 0.00722
epssPercentile: 0.52553
ingestedAt: '2026-07-16T12:53:56.090Z'
---

## Overview

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).

## Affected

- `unbound < 1.25.1`

## Remediation

Upgrade past the affected range:

- `unbound 1.25.1`