---
id: CVE-2026-26018
title: CoreDNS is a DNS server that chains plugins
summary: >-
  CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a denial
  of service vulnerability exists in CoreDNS's loop detection plugin that allows
  an attacker to crash the DNS server by sending specially crafted DNS queries.
  T…
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-337
  - CWE-400
  - CWE-770
  - CWE-1241
vendor: coredns.io
product: coredns
affected:
  - coredns < 1.14.2
patched:
  - coredns 1.14.2
published: '2026-03-06'
updated: '2026-07-09'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-26018'
references:
  - url: 'https://github.com/coredns/coredns/releases/tag/v1.14.2'
    label: security-advisories@github.com
  - url: 'https://github.com/coredns/coredns/security/advisories/GHSA-h75p-j8xm-m278'
    label: security-advisories@github.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:25127'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/errata/RHSA-2026:36873'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/errata/RHSA-2026:8151'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/security/cve/CVE-2026-26018'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2445242'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26018.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
epss: 0.00757
epssPercentile: 0.53259
ingestedAt: '2026-07-10T01:55:22.951Z'
---

## Overview

CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a denial of service vulnerability exists in CoreDNS's loop detection plugin that allows an attacker to crash the DNS server by sending specially crafted DNS queries. The vulnerability stems from the use of a predictable pseudo-random number generator (PRNG) for generating a secret query name, combined with a fatal error handler that terminates the entire process. This issue has been patched in version 1.14.2.

## Affected

- `coredns < 1.14.2`

## Remediation

Upgrade past the affected range:

- `coredns 1.14.2`