CVE-2026-26017

CoreDNS ACL Bypass

Published: Mar 6, 2026Updated: Jul 15, 2026 Sources: CVE List NVD GHSACWE-367

7.7HIGH

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:CScope

Changed

Impact

C:HConfidentiality

High

I:NIntegrity

None

A:NAvailability

None

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Weaknesses

CWE-367

Affected Products

coredns.io

oss-projectaka coredns

corednsOn-prem

Networking Infrastructure / dns-dhcp-ntp

package-ecosystem

github.com/coredns/coredns

OSS Libraries

and 1 more affected products View all →

Exploitability

Official Patch Available

Workaround Available

Is your org exposed to CVE-2026-26017?Request an assessment to establish which checks are appropriate for your systems. Check my exposure

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Privilege Escalation

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References

https://github.com/coredns/coredns/security/advisories/GHSA-c9v3-4pv7-87pr

github.com

https://github.com/coredns/coredns/releases/tag/v1.14.2

github.com

https://nvd.nist.gov/vuln/detail/CVE-2026-26017

nvd.nist.gov

and 7 more references View all →

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