Kubernetes Denied Service Account Request via Unusual User Agent
This rule detects when a service account makes an unauthorized request for resources from the API server via an unusual user agent. Service accounts follow a very predictable pattern of behavior. A service account…
Description
This rule detects when a service account makes an unauthorized request for resources from the API server via an unusual user agent. Service accounts follow a very predictable pattern of behavior. A service account should never send an unauthorized request to the API server. This behavior is likely an indicator of compromise or of a problem within the cluster. An adversary may have gained access to credentials/tokens and this could be an attempt to access or create resources to facilitate further movement or execution within the cluster.
Detection logic
Its licence does not clear it for publishing here
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Detection requirements
- Platform
- Containers
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- event_index
Known benign triggers
- Unauthorized requests from service accounts are normal and expected behavior. Analyze the user agent, pod and other node information to determine if the request is legitimate.
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 |
|---|---|
| kubernetes.io/docs/reference/access-authn-authz/authentication/#service-account-tokens | 7 |
| research.nccgroup.com/2021/11/10/detection-engineering-for-kubernetes-clusters/#part3-kubernetes-detections | 4 |
From the source
- At source
- Open at source
- Upstream identifier
- 63c056a0-339a-11ed-a261-0242ac120002
- Tagged by the source as
- Data Source: KubernetesDomain: KubernetesResources: Investigation GuideTactic: DiscoveryUse Case: Threat Detection
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Aug 27, 2026
- Version
- 1