AWS EKS API Request Impersonating Privileged Identity

Last updated 3 days ago on 2026-10-20

Created 3 months ago on 2026-08-03

About

Detects Kubernetes API requests where a user is impersonating a privileged cluster identity such as system:kube-controller-manager, system:admin, system:anonymous, or a member of the system:masters group. These identities have broad cluster-wide permissions including unrestricted access to all secrets, the ability to create tokens for any service account, schedule pods on any node, and modify RBAC policies. An attacker impersonating system:masters gains full cluster-admin equivalent access, while impersonating system:kube-controller-manager grants access to every secret in every namespace and the ability to mint service account tokens for lateral movement.

Tags

Domain: CloudDomain: ContainersPlatform: AWSPlatform: KubernetesData Source: AWSData Source: Amazon Web ServicesData Source: Kubernetes API Server Audit LogsService: AWS EKSUse Case: Threat DetectionTactic: Privilege EscalationTactic: Defense EvasionRule Type: Custom Query (KQL)Profile: BetaLanguage: kuery

Severity

high

Risk Score

MITRE ATT&CK™

Privilege Escalation (TA0004)(external, opens in a new tab or window)

↳ Access Token Manipulation (T1134)(external, opens in a new tab or window)

Defense Evasion (TA0005)(external, opens in a new tab or window)

↳ Access Token Manipulation (T1134)(external, opens in a new tab or window)

False Positive Examples

Break-glass admin tooling, security scanners, or approved controllers that legitimately use impersonation with privileged targets may match if not covered by exclusions. Map expected callers and expand `not user.name` filters as needed for your environment.

License

Elastic License v2(external, opens in a new tab or window)

Definition

Rule Type: Query (Kibana Query Language)
Integration Pack: Prebuilt Security Detection Rules
Index Patterns: logs-aws.eks_audit-*
Related Integrations: aws(external, opens in a new tab or window)
Query

✄𐘗text code block:
✄𐘗data_stream.dataset:aws.eks_audit and
aws.eks.audit.impersonatedUser.username:(* and not ("eks-event-service:event-controller" or eks\:*)) and
aws.eks.audit.annotations.authorization_k8s_io/decision:allow and
aws.eks.audit.verb:(create or delete or get or list or patch or update) and
(aws.eks.audit.impersonatedUser.username:(admin or cluster-admin or kubernetes-admin or "system:admin" or "system:anonymous" or "system:apiserver" or "system:kube-controller-manager" or "system:kube-proxy" or "system:kube-scheduler" or "system:volume-scheduler" or system\:node\:* or system\:serviceaccount\:kube-system\:*) or aws.eks.audit.impersonatedUser.groups:(cluster-admin or "system:cluster-admins" or "system:masters")) and
not user.name:("system:kube-controller-manager" or "system:kube-scheduler" or arn\:aws\:iam\:*\:role/aws-service-role* or arn\:aws\:sts\:*\:assumed-role/AWSServiceRoleForAmazonEKS* or arn\:aws\:sts\:*\:assumed-role/AWSServiceRoleForAmazonEKSNodegroup* or eks\:* or system\:node\:* or system\:serviceaccount\:kube-system\:*)

Install detection rules in Elastic Security

Detect AWS EKS API Request Impersonating Privileged Identity in the Elastic Security detection engine by installing this rule into your Elastic Stack.

To setup this rule, check out the installation guide for Prebuilt Security Detection Rules(external, opens in a new tab or window).