In order to solve this machine, we first need to understand Secure Shell (SSH) and how it works. SSH is a cryptographic network protocol that provides a secure channel for communication between two devices over an unsecured network. It replaced the insecure protocol known as Telnet. Furthermore, SSH has become the de facto standard for secure remote access, system administration, and file transfer across the Internet.
How Does it Work?
At its core, SSH operates using a client-server model. When a user initiates an SSH session, the client software establishes a secure connection to the SSH server. This connection is encrypted using cryptographic algorithms, ensuring the confidentiality and integrity of the data transmitted between the client and server.
One of SSH’s key features is its ability to authenticate users securely. SSH supports various authentication methods, including password-based, public-key, and multi-factor authentication (MFA). Public-key authentication, in particular, enhances security by allowing users to authenticate without transmitting passwords over the network.
Key Features of SSH
- Encryption: SSH encrypts all data transmitted between the client and server, protecting it from eavesdropping and tampering by malicious actors.
- Authentication: SSH supports multiple authentication methods, including passwords, public-key cryptography, and MFA, allowing organizations to choose the most appropriate method based on their security requirements.
- Port Forwarding: SSH enables secure port forwarding, allowing users to securely access services running on remote servers as if they were local.
- Tunneling: SSH supports tunneling of other protocols, such as HTTP, FTP, and VNC, over its secure channel, providing a secure pathway for various network services.
- Remote Command Execution: SSH allows users to execute commands on remote servers securely, making it an invaluable tool for system administration and automation tasks.
Use Cases of SSH
- Remote Server Administration: System administrators use SSH to manage servers and network devices remotely, perform routine maintenance tasks, and troubleshoot issues without compromising security.
- Secure File Transfer: SSH’s built-in file transfer capabilities, using tools like SCP (Secure Copy) and SFTP (SSH File Transfer Protocol), enable secure transfer of files between hosts.
- Secure Shell Tunnels: Organizations use SSH tunnels to securely access internal services, such as databases and web servers, from external networks, protecting sensitive data from unauthorized access.
SSH Syntax
The basic syntax of this tool is:
e@e:~$ ssh user@host -p [port number]
where the user is the username on the remote machine, the host is the address or hostname of the remote machine and the port number we are using in order to connect to the machine.
Giving Information
The main goal of this level is to connect to the targeted machine using SSH. Now, as shown in the Figure below, the machine has the following details:
- Host: bandit.labs.overthewire.org
- Port: 2220
- Username: bandit0
- Password: bandit0
Accessing The Machine
Let us try to access the machine using the command we learned above:
e@e:~$ ssh bandit0@bandit.labs.ovedrthewire.org -p 2220
As we can see in Figure 2, after running the previous command, we will get the following output:
The server will prompt us for credentials, and since we already have them, we will input them directly, which is “bandit0“.
As shown, we have successfully connected to the machine using SSH.
We have successfully accessed the first machine using SSH and are now poised to continue our journey to the next bandit! For a glimpse into the walkthrough for the next Bandit, click here.