The command injecion is an attack in which the goal is the execution of arbitrary commands on the host operating system via a vulnerable application. Command injection attacks are possible when an application passes unsafe user supplied data (forms, cookies, HTTP headers etc.) to a system shell. In the first step, the attacker needs to inspect the functioning of the web app in order to find possible injection points. When we start the application we can see that there are two forms: the first one to select the logs and second one to select the color in the logs.