Headless Kali Linux RPi Setup Guide

A "headless" setup means any host on the network can remotely connect to a headless client via SSH or VNC. This removes the need for peripherals to operate a server.
In this walkthrough, we will be setting up a remote Kali Linux setup on ARM architecture. (RPi 1, 2, 3, 4, 400, Zero, Zero W)

Download Kali-ARM image

Initially, we need to download a Kali Linux image that is compatible with ARM architecture.

Download Link

Load the image into any image flasher

For this step, we're going to use Etcher. Head over to this repo and follow the guide to install and configure Etcher on your OS.

Make sure your chosen storage (SSD/Micro SD card) is inserted.
Start Etcher
Select the Kali-ARM image
Select the storage
Flash

Boot into your Raspberry Pi

The default username is 'kali' and the password is 'kali'.
Remove unnecessary packages and apt cache to allow for upgrade:

sudo apt autoremove && sudo apt autoclean

Make sure you are connected to the network, then run the updates:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade

Update kali's password (for obvious reasons):

passwd kali

Install OpenSSH Server

Run the following to install OpenSSH and update the runlevels to allow SSH on boot:

sudo apt-get install openssh-server
update-rc.d -f ssh remove
update-rc.d -f ssh defaults

Change the default keys:

cd /etc/ssh
mkdir insecure_old
mv ssh_host* insecure_old
dpkg-reconfigure openssh-server

Restart the SSH service:

sudo service ssh restart
update-rc.d -f ssh enable 2 3 4 5

Verify SSH functionality:

sudo service ssh status

The output should look similar to this:

● ssh.service - OpenBSD Secure Shell server
     Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: disabled)
     Active: active (running) since Sun 2021-08-01 19:18:18 UTC; 1 day 8h ago

If the SSH service is NOT running:

sudo service ssh start

Configure wireless network availability on boot

Navigate into this directory:

cd /etc/NetworkManager/system-connections

Verify that a .nmconnection file exists, containing the connected wireless network's information. You can copy the template.nmconnection from this repo into this directory and replace the template and password fields if the file does NOT exist.
Change the permissions of this file:

sudo chmod 600 yournetwork.nmconnection

Next, we're going to edit NetworkManager.conf:

sudo nano /etc/NetworkManager/NetworkManager.conf

Change the contents of the file to this (managed=true):

[main]
plugins=ifupdown,keyfile

[ifupdown]
managed=true

Next, we're going to edit /etc/network/interfaces.
Add these lines:

auto wlan0
iface wlan0 inet dhcp

Configure auto-login

To make our Kali completely headless, we need to edit /etc/lightdm/lightdm.conf:

sudo nano /etc/lightdm/lightdm.conf

Find these lines:

#autologin-user =
#autologin-user-timeout =

There will be 4 lines (2 sets of occurences) of these same lines in this file. Change all occurences to this:

autologin-user=kali
autologin-user-timeout=0

Find this line and uncomment:

#pam-autologin-service=lightdm-autologin

You can also take a look at lightdm.conf in this repo, copy and paste everything to your own lightdm.conf file.

Done! Run ifconfig to find Kali's IP. We're going to need this to SSH into it. You can now boot up your Pi without a monitor or keyboard and connect via SSH:

ssh kali@<ip-address>

prodseanb/headless-kali-RPi