Kubernetes Service Account Created in Kube Namespace

Classification:

attack

Tactic:

TA0003-persistence

Technique:

T1136-create-account

Set up the kubernetes integration.

Goal

Detect when a user is creating a service account in one of the Kubernetes default namespaces.

Strategy

This rule monitors when a create (@http.method:create) action occurs for a service account (@objectRef.resource:serviceaccounts) within either of the kube-system or kube-public namespaces.

The only users creating service accounts in the kube-system namespace should be cluster administrators. Furthermore, it is best practice to not run any cluster critical infrastructure in the kube-system namespace.

The kube-public namespace is intended for kubernetes objects which should be readable by unauthenticated users. Thus, a service account should likely not be created in the kube-public namespace.

Triage and response

Determine if the user should be creating this new service account in one of the default namespaces.

Changelog

• 21 September 2022 - Tuned rule to remove system and EKS service account creations, increased severity, added decrease on environment flag.
• 17 October 2022 - Updated tags.