Medium severity · published Mar 6, 2026
CVE-2026-26017
CoreDNS ACL Bypass
6.3
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
coredns · coredns
< 1.14.2 · source: vendor, NVD
RH
Red Hat Advanced Cluster Management for Kubernetes 2.13 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Advanced Cluster Management for Kubernetes 2.14 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Advanced Cluster Management for Kubernetes 2.15 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Connectivity Link 1 · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-26017
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-26017
Product
https://github.com/coredns/coredns/releases/tag/v1.14.2
Mitigation
https://github.com/coredns/coredns/security/advisories/GHSA-c9v3-4pv7-87pr
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:25127
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:36873
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:8151
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-26017
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