Have you ever worked with a remote computer? A remote computer is a computer that you can access through a network link on another computer. You have no physical access to the computer, These connections are made through a network that is connected to the remote computer and the computer that’s used to access it.

Sometimes, however, the remote computers are hard to reach. There might be firewall issues or a local admin set up issue that may be hampering your device’s connection to the remote computer. One of the ways that you can fix the issues with connecting your device to the remote computer, is by reverse SSH tunneling.

What is Reverse SSH Tunneling?

You can usually establish an SSH connection on your device (the local computer) and connect to the remote computer, but sometimes this might not be an option. Sometimes you can’t establish an SSH connection straight to the remote computer. SSH tunneling connects your device to the remote computer, but with reverse SSH tunneling, the remote computer connects to you. This can be used if the connection between the two computers are straightforward.

The original connection came from the remote computer and you have use that original connection, except you have to go in the other connection. SSH is secure, so any connection that you establish in that secure connection is also secure. The original connection is a “private tunnel.”

How Does Reverse SSH Forwarding Work?

Reverse SSH Tunneling is dependent on a remote computer. The remote computer uses the connection that was establish so that it can listen for any connection requests that might come from your computer, the local computer. There’s a network port on the local computer that the remote computer can listen to. If the remote computer detects a request from that port, then it can relay the information about that request to itself through that connection. This is now the new connection from the local computer to the remote computer.

What is it used for?

SSH tunneling is mainly used in corporate environments because they use mainframe systems as backends for their applications because the applications themselves don’t have a lot of security support. SSH tunneling is a great cost- effective way to add security since modifying the applications or application servers might be impractical with the code changes that might have to occur. An example of this is country- wide ATM networks use tunneling for security reasons.

Risks of SSH Tunneling

The benefits of the security of SSH tunneling can be also a huge risk. SSH connections are encrypted and this means that the contents of the tunnel are invisible to any of the monitoring and traffic filtering that you would usually do. This makes it have the potential to be used for malicious intents, like retrieving protected data.

You could also hide communications and stolen data from the local computer in the tunnel. What’s even worse is that these SSH tunneling attacks can be used to hide the source of the breach, which hides tracks. Outsiders can run attacks against protocols and probe for the correct login credentials.

Hopefully, you learned all you needed to about SSH forwarding. There are other forms of networking data that might be more suitable to your circumstance.