CVE-2026-26017

CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a logical vulnerability in CoreDNS allows DNS access controls to be bypassed due to the default execution order of plugins. Security plugins such as acl are evaluated before the rewrite plugin, resulting in a Time-of-Check Time-of-Use (TOCTOU) flaw. This issue has been patched in version 1.14.2.

CVSS v3 7.7 HIGH

7.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.1 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/coredns/coredns/releases/tag/v1.14.2	Product Release Notes
https://github.com/coredns/coredns/security/advisories/GHSA-c9v3-4pv7-87pr	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:coredns.io:coredns:*:*:*:*:*:*:*:*

History

17 Jun 2026, 10:25

Type	Values Removed	Values Added
Summary		(es) CoreDNS es un servidor DNS que encadena plugins. Antes de la versión 1.14.2, una vulnerabilidad lógica en CoreDNS permite que los controles de acceso DNS sean eludidos debido al orden de ejecución predeterminado de los plugins. Plugins de seguridad como acl son evaluados antes del plugin rewrite, lo que resulta en una falla de Tiempo de Verificación Tiempo de Uso (TOCTOU). Este problema ha sido parcheado en la versión 1.14.2.

09 Mar 2026, 20:31

Type	Values Removed	Values Added
First Time		Coredns.io coredns Coredns.io
CPE		cpe:2.3:a:coredns.io:coredns::::::::
References	~~() https://github.com/coredns/coredns/releases/tag/v1.14.2 -~~	() https://github.com/coredns/coredns/releases/tag/v1.14.2 - Product, Release Notes
References	~~() https://github.com/coredns/coredns/security/advisories/GHSA-c9v3-4pv7-87pr -~~	() https://github.com/coredns/coredns/security/advisories/GHSA-c9v3-4pv7-87pr - Mitigation, Vendor Advisory

06 Mar 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-03-06 16:16

Updated : 2026-06-17 10:25

NVD link : CVE-2026-26017

Mitre link : CVE-2026-26017

CVE.ORG link : CVE-2026-26017

JSON object : View

Products Affected

coredns.io

coredns

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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