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Fencer Vulns
low 3.7

CVE-2026-62994 json

CoreDNS `k8s_external` headless AXFR can emit an empty transfer batch that panics the `transfer` plugin

published 2026-07-16 3 mo ago modified 2026-10-19 20 d ago also EUVD-2026-45018 , GHSA-74w3-63xv-x9mv , GO-2026-6805

cvss
3.7
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 40%
public exploits
0
none known

Summary

CoreDNS is a DNS server written in Go. From 1.9.4 until 1.14.5, a network DNS client allowed to request AXFR for a CoreDNS zone can trigger a panic when CoreDNS is configured with k8s_external headless-service zone transfers and Kubernetes contains a headless service endpoint with no declared ports; plugin/kubernetes/object/endpoint.go creates Port: -1, plugin/k8s_external/msg_to_dns.go skips that service, plugin/k8s_external/transfer.go sends an empty []dns.RR batch, and plugin/transfer/transfer.go indexes records[0] without checking the batch is non-empty. This issue is fixed in version 1.14.5.

Patch / fix

  • go github.com/coredns/coredns 1.14.5
  • coredns.io coredns 1.14.5
  • coredns Azure Linux 3.0 1.11.4-20

azure linux advisories AZL-92895

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-62994 updated cvss 3.7

coredns: CoreDNS: Denial of Service via crafted AXFR request with k8s_external headless-service

  • Red Hat Advanced Cluster Management for Kubernetes 2 rhacm2/lighthouse-agent-rhel9, rhacm2/lighthouse-coredns-rhel9 Red Hat OpenShift Container Platform 4 openshift4/ose-coredns, openshift4/ose-coredns-rhel9
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Connectivity Link 1 rhcl-1/coredns-rhel9
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.46% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/coredns/coredns/security/advisories/GHSA-74w3-63xv-x9mv referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
GitHub 3.1 3.7 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem package affected fixed in
go github.com/coredns/coredns
>=1.9.4, <1.14.5
1.14.5

Affected products

  • coredns coredns

Classification

Weakness
  • CWE-248 Uncaught Exception
  • CWE-755 Improper Handling of Exceptional Conditions

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.