GKE Forbidden Request from Unusual User Agent
Detects the first occurrence of a failed GKE API request from a previously unseen user agent. Adversary tooling often uses non-standard clients; combined with authorization failures this can indicate RBAC probing or…
Description
Detects the first occurrence of a failed GKE API request from a previously unseen user agent. Adversary tooling often uses non-standard clients; combined with authorization failures this can indicate RBAC probing or exploitation attempts.
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
- New internal tools, SDKs, or CI runners introduce novel user agents. Baseline expected clients, then exclude stable automation UAs after review.
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 |
|---|---|
| cloud.google.com/kubernetes-engine/docs/how-to/audit-logging | 12from 2 sources |
| kubernetes.io/docs/reference/access-authn-authz/authorization/ | 5 |
From the source
- At source
- Open at source
- Upstream identifier
- e1147459-a3e1-4bdc-bab9-965807801774
- Tagged by the source as
- Data Source: GCPData Source: Google Cloud PlatformDomain: CloudDomain: ContainersDomain: KubernetesNoise: LowPerformance: FastPlatform: GCPPlatform: KubernetesResources: Investigation GuideRule Type: New TermsTactic: DiscoveryTactic: ExecutionUse Case: Threat Detection
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Sep 20, 2026
- Version
- 3