CVE-2026-26017

CoreDNS ACL Bypass

MEDIUM
6.3
CVSS Score
Published: March 6, 2026 at 03:36 PM UTC
Updated: July 15, 2026 at 02:18 AM UTC
3 products affected across 2 vendorsCorednsIo CorednsConnectivity Link

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Severity
MEDIUM6.3
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.14.2
Affected range stops below 1.14.2, so it looks safe — our inference, not a vendor statement
v < 1.14.2
Affected range stops below 1.14.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (8)

x_refsource_CONFIRMMitigationVendor Advisory
Source: cverecord
https://github.com/coredns/coredns/security/advisories/GHSA-c9v3-4pv7-87pr
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/coredns/coredns/releases/tag/v1.14.2
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:25127
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:8151
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/security/cve/CVE-2026-26017
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://bugzilla.redhat.com/show_bug.cgi?id=2445244
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/errata/RHSA-2026:36873

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
HIGH
Privileges
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-367

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