Bind Address Not Properly Set

• Query id: 46a2e9ec-6a5f-4faa-9d39-4ea44d5d87a2
• Query name: Bind Address Not Properly Set
• Platform: Kubernetes
• Severity: High
• Category: Networking and Firewall
• URL: Github

Description

When using kube-controller-manager or kube-scheduler commands, the '--bind-address' should not be set to 127.0.0.1
Documentation

Code samples

Code samples with security vulnerabilities

Positive test num. 1 - yaml file

apiVersion: v1
kind: Pod
metadata:
  name: command-demo
  labels:
    purpose: demonstrate-command
spec:
  containers:
    - name: command-demo-container
      image: gcr.io/google_containers/kube-controller-manager-amd64:v1.6.0
      command: ["kube-controller-manager"]
      args: ["--bind-address=127.0.0.1"]
  restartPolicy: OnFailure

Positive test num. 2 - yaml file

apiVersion: v1
kind: Pod
metadata:
  name: command-demo
  labels:
    purpose: demonstrate-command
spec:
  containers:
    - name: command-demo-container
      image: gcr.io/google_containers/kube-controller-manager-amd64:v1.6.0
      command: ["kube-controller-manager","--bind-address=127.0.0.1"]
      args: []
  restartPolicy: OnFailure

Positive test num. 3 - yaml file

apiVersion: v1
kind: Pod
metadata:
  labels:
    component: kube-scheduler
    tier: control-plane
  name: kube-scheduler
  namespace: kube-system
spec:
  selector:
    matchLabels:
      app: kube-controller-manager
  template:
    metadata:
      labels:
        app: kube-controller-manager
  containers:
    - name: command-demo-container
      image: k8s.gcr.io/kube-scheduler:v1.19.0
      command: ["kube-scheduler"]
      args: ["--bind-address=127.0.0.1"]
  restartPolicy: OnFailure

Positive test num. 4 - yaml file

apiVersion: v1
kind: Pod
metadata:
  labels:
    component: kube-scheduler
    tier: control-plane
  name: kube-scheduler
  namespace: kube-system
spec:
  selector:
    matchLabels:
      app: kube-controller-manager
  template:
    metadata:
      labels:
        app: kube-controller-manager
  containers:
    - name: command-demo-container
      image: k8s.gcr.io/kube-scheduler:v1.19.0
      command: ["kube-scheduler","--bind-address=127.0.0.1"]
      args: []
  restartPolicy: OnFailure

Code samples without security vulnerabilities

Negative test num. 1 - yaml file

apiVersion: v1
kind: Pod
metadata:
  name: command-demo
  labels:
    purpose: demonstrate-command
spec:
  containers:
    - name: command-demo-container
      image: gcr.io/google_containers/kube-controller-manager-amd64:v1.6.0
      command: ["kube-controller-manager","--bind-address=0.0.0.0"]
      args: []
  restartPolicy: OnFailure

Negative test num. 2 - yaml file

apiVersion: v1
kind: Pod
metadata:
  name: command-demo
  labels:
    purpose: demonstrate-command
spec:
  containers:
    - name: command-demo-container
      image: gcr.io/google_containers/kube-controller-manager-amd64:v1.6.0
      command: ["kube-controller-manager"]
      args: []
  restartPolicy: OnFailure

Negative test num. 3 - yaml file

apiVersion: v1
kind: Pod
metadata:
  labels:
    component: kube-scheduler
    tier: control-plane
  name: kube-scheduler
  namespace: kube-system
spec:
  selector:
    matchLabels:
      app: kube-controller-manager
  template:
    metadata:
      labels:
        app: kube-controller-manager
  containers:
    - name: command-demo-container
      image: k8s.gcr.io/kube-scheduler:v1.19.0
      command: ["kube-scheduler"]
      args: []
  restartPolicy: OnFailure

Negative test num. 4 - yaml file

apiVersion: v1
kind: Pod
metadata:
  labels:
    component: kube-scheduler
    tier: control-plane
  name: kube-scheduler
  namespace: kube-system
spec:
  selector:
    matchLabels:
      app: kube-controller-manager
  template:
    metadata:
      labels:
        app: kube-controller-manager
  containers:
    - name: command-demo-container
      image: k8s.gcr.io/kube-scheduler:v1.19.0
      command: ["kube-scheduler","--bind-address=0.0.0.0"]
      args: []
  restartPolicy: OnFailure