GKE CoreDNS or Kube-DNS Configuration Modified
Detects modifications to the CoreDNS or kube-dns ConfigMap in the kube-system namespace on GKE. These ConfigMaps control cluster DNS resolution for all pods. An attacker who modifies the CoreDNS Corefile can redirect…
Description
Detects modifications to the CoreDNS or kube-dns ConfigMap in the kube-system namespace on GKE. These ConfigMaps control cluster DNS resolution for all pods. An attacker who modifies the CoreDNS Corefile can redirect internal service DNS names to attacker-controlled IP addresses, enabling man-in-the-middle attacks against the Kubernetes API server, database services, and other internal endpoints. Pods that resolve service names via cluster DNS will transparently connect to the attacker instead of the legitimate service, allowing interception of service account tokens, database credentials, and API traffic. DNS poisoning at the cluster level is particularly dangerous because it affects every pod in every namespace simultaneously and does not require any modification to the victim workloads. CoreDNS configuration changes are rare in normal operations and any unexpected modification should be investigated immediately.
Detection logic
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Detection requirements
- Platform
- LinuxmacOSWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- event_index
Known benign triggers
- Cluster administrators may legitimately update CoreDNS configuration for forwarding, stub domains, or cluster DNS troubleshooting. Baseline approved operators and automation identities; tune exclusions for known change pipelines.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| coredns.io/plugins/rewrite/ | 2 |
| kubernetes.io/docs/tasks/administer-cluster/dns-custom-nameservers/ | 3 |
From the source
- At source
- Open at source
- Upstream identifier
- 80528e81-949f-4d38-b0c7-aef4b160212e
- Tagged by the source as
- Data Source: GCPData Source: Google Cloud PlatformDomain: CloudDomain: ContainersDomain: KubernetesNoise: UnknownPerformance: NormalPlatform: GCPPlatform: KubernetesResources: Investigation GuideRule Type: Custom Query (KQL)Tactic: ImpactUse Case: Threat Detection
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Sep 20, 2026
- Version
- 3