Ensure that the --bind-address argument is set to 127.0.0.1 (Scheduler)

Do not bind the scheduler service to non-loopback insecure addresses. The Scheduler API service which runs on port 10251/TCP by default is used for health and metrics information and is available without authentication or encryption. As such it should only be bound to a localhost interface, to minimize the cluster's attack surface

Suggest Edits

Risk Level: High
Cloud Entity: Pods
CloudGuard Rule ID: D9.K8S.NET.21
Covered by Spectral: Yes
Category: Compute

GSL LOGIC

KubernetesPod where labels contain [value='kube-scheduler'] and namespace = 'kube-system' should have spec.containers with [(parsedArgs contain [key like 'bind-address' and value = '127.0.0.1']) or (parsedArgs contain-none [key like 'bind-address'])]

REMEDIATION

Edit the Scheduler pod specification file /etc/kubernetes/manifests/kube-scheduler.yaml on the master node and ensure the correct value for the --bind-address parameter

References

https://kubernetes.io/docs/reference/command-line-tools-reference/kube-scheduler/

Pods

Pods are the smallest deployable units of computing that can be created and managed in Kubernetes.A Pod is a group of one or more containers (such as Docker containers), with shared storage/network, and a specification for how to run the containers.

Compliance Frameworks

CIS Kubernetes Benchmark v1.20
CIS Kubernetes Benchmark v1.23
CIS Kubernetes Benchmark v1.24
CIS Kubernetes Benchmark v1.5.1
CIS Kubernetes Benchmark v1.6.1
Kubernetes NIST.SP.800-190
Kubernetes v.1.13 CloudGuard Best Practices
Kubernetes v.1.14 CloudGuard Best Practices

Updated over 1 year ago