When trying to learn how to scan and exploit a Linux machine, one major problem we encounter is where to try. For this purpose, the Metasploit team has developed and released a virtual machine called Metasploitable. This machine has been made vulnerable purposefully, having many services running unpatched. Due to this, it has become a great platform for practicing or developing penetration testing skills. In this section, we will learn how to scan a Linux system and then, using the scanning result, how to find a service that is vulnerable. Using that vulnerable service, we shall gain root access to the system.