Silo focuses mainly on leveraging Oracle to obtain a shell and escalate privileges. It was intended to be completed manually using various tools, however Oracle Database Attack Tool greatly simplifies the process, reducing the difficulty of the machine substantially.

Grandpa is one of the simpler machines on Hack The Box, however it covers the widely-exploited CVE-2017-7269. This vulnerability is trivial to exploit and granted immediate access to thousands of IIS servers around the globe when it became public knowledge.

Arctic is fairly straightforward, however the load times on the web server pose a few challenges for exploitation. Basic troubleshooting is required to get the correct exploit functioning properly.

Granny, while similar to Grandpa, can be exploited using several different methods. The intended method of solving this machine is the widely-known Webdav upload vulnerability.

Bastard is not overly challenging, however it requires some knowledge of PHP in order to modify and use the proof of concept required for initial entry. This machine demonstrates the potential severity of vulnerabilities in content management systems.

Devel, while relatively simple, demonstrates the security risks associated with some default program configurations. It is a beginner-level machine which can be completed using publicly available exploits.

Jarvis is a medium difficulty Linux box running a web server, which has DoS and brute force protection enabled. A page is found to be vulnerable to SQL injection, which requires manual exploitation. This service allows the writing of a shell to the web root for the foothold. The www user is allowed to execute a script as another user, and the script is vulnerable to command injection. On further enumeration, systemctl is found to have the SUID bit set, which is leveraged to gain a root shell.

Networked is an Easy difficulty Linux box vulnerable to file upload bypass, leading to code execution. Due to improper sanitization, a crontab running as the user can be exploited to achieve command execution. The user has privileges to execute a network configuration script, which can be leveraged to execute commands as root.