Autossh reverse tunnel raspberry pi install#
Autossh reverse tunnel raspberry pi password#

You paste the contents of your public key to the authorized_keys file on the server you want to login to. You could use the ssh-keygen command or you could use a tool like PuTTYgen which you probably already have.Īt a very basic level how this works is that you generate a public and private key pair which are mathematically linked. Generating and implementing public/private keys is very easy and there are a number of ways we can do it. If we want the Raspberry Pi to automatically establish a background SSH connection to our server then we need to use a password-less approach i.e., public key authentication.

Autossh reverse tunnel raspberry pi password#

One is using a password and the other is using a public/private key pair. There are two ways we can authenticate to an SSH server. passwd root Generating Public/Private Key Pair

I ran the VM image on VMware Workstation – I’ll call this the C&C (command and control) server from this point onĬhange the default credentials from root:toor to something more secure especially if you decide to permit password-logins later on.

Autossh reverse tunnel raspberry pi install#

Install the appropriate Kali image on the machine that the Raspberry Pi will tunnel to.Use Win32 Disk Imager to write the Kali image to the SD card Install the appropriate Kali ARM image on your Raspberry Pi’s micro SD card.

Server can now talk to and take control of Client using the reverse SSH tunnelīefore we begin configuring the client and server we should get some basics out of the way first.Firewall knows no better as the SSH connection is established within the SSL tunnel. Client establishes reverse SSH tunnel with the server.Firewall permits the traffic as it looks like normal SSL traffic Client establishes SSL tunnel with server over port 443.We’ll be using it to tunnel our SSH connection so that it looks like normal SSL traffic. This is where stunnel comes in handy – stunnel acts as a SSL wrapper which you can use to tunnel almost anything through. You’ll find a subset of those IT departments will have the resources available to use some sort of IDS/IPS/NGFW to do deep packet inspection so even if you SSH’d over port 443, the device performing the inspection will identify the traffic as SSH and drop it. Now you’ll find that most (I hope) IT departments will have port 22 blocked. You can then piggyback off this connection to talk directly to the client on the network all without NAT’ing/opening any ports on the firewall. The post was written with the intention of aiding security researchers, testers and people who are simply intrigued and want to learn the technology in order to improve the security stature of their own networks.Ī reverse tunnel is one where the client (Raspberry Pi in this case) makes a connection out from the target network to your server.

You don’t even need a power socket nearby as you can use a powerbank with enough capacity to last you a good few hours enough time to find an exploit/vulnerability on the network and hop on to a more permanent host.įirst let me start off by saying that this post is for educational purposes only and that you should always seek permission to use/abuse a network that you are not responsible for. In my set-up I used the Raspberry Pi 3 as the client because it’s small, inexpensive and inconspicuous great for penetration testers in the field who want to be in and out of an environment in under a minute. The reverse SSH tunnel will be encapsulated within a SSL tunnel over port 443 to evade network security appliances/firewalls. In this blog I will go through the steps necessary to set-up an automatic reverse SSH tunnel between a client machine sitting in a restricted environment and a server that you control in your home/office/ cloud.