Kube Hunter is an open source tool maintained by Aqua Security, which hunts weak kubernetes clusters.
The tool was developed to increase awareness and visibility for security issues in Kubernetes environments,

Developers, please read Guidelines For Developing Your First Kube Hunter Module

by default, without any special flags, Kube Hunter will scan all of your machine's network interfaces for open kubernetes services.

To specify a specific cidr to scan, use the --cidr option. Example:
./kube-hunter.py --cidr 192.168.0.0/24

To specify remote machines for hunting, you can use the --remote option. Example:
./kube-hunter.py --remote some.node.com

Active hunting is an option, in which Kube Hunter will exploit vulnerabilities it found, to further findind more vulnerabilities.
The main differences between normal active hunting, is that a normal hunt will never change state of the cluster. while active hunting can do many harsh operations on the cluster.
When active, evidences of vulnerabilities will be added to the final report
To active hunt a cluster, use the --active flag. Example:
./kube-hunter.py --remote some.domain.com --active

To control logging, you can specify a log level, using the --log option. Example:
./kube-hunter.py --active --log WARNING
Available log levels are:

DEBUG
INFO (default)
WARNING

--
To see only a mapping of your nodes network, run with --mapping option. Example:
./kube-hunter.py --cidr 192.168.0.0/24 --mapping
This option will output all the kubernetes nodes Kube-Hunter has found

There are three methods in which you can deploy Kube Hunter with:

• python 2.7
• pip

Installing modules:

cd ./kube-hunter
pip install -r requirements.txt

Running:
./kube-hunter.py

To run Kube Hunter's container:

Linux:
docker run --rm --network host aquasec/kube-hunter
Windows:
docker run --rm aquasec/kube-hunter --cidr 192.168.0.0/24

Docker for Windows forces us to use a manual cidr, as to it's limitations

This option lets you discover what running a malicous container can do/discover on your cluster.
Kube Hunter will scan your cluster from the inside, using default kubernetes pod access settings, usually, revealing significantly more services and vulnerabilities
To run Kube Hunter as a pod, kubectl create the following yaml file.

---
apiVersion: v1
kind: Pod
metadata:
  name: kube-hunter
spec:
  containers:
  - name: kube-hunter
    image: aquasec/kube-hunter
    command: ["python", "kube-hunter.py"]
    args: ["--pod"]
  restartPolicy: Never   # for Kube Hunter to hunt once