The competition has 9 levels. Each level is in the form of a password-protected zipfile. To unlock it, you must find the flag at each level and enter it as the password. To proceed, you will have to traverse the levels using various Linux commands, and find the flag at each level. Each level also has a README file, with some info/hints about the level.
To get you started, we've compiled a list of basic commands that you'll need to traverse the folders:
- ls/dir - Display the contents of the given directory/folder.
- cd <folder_name> - Open the given folder.
- cd .. - Return to the previous folder.
- nano <file_name> - Open the given file in the 'nano' text editor.
- eog <image_name> - Open the given image in the default image viewing application.
- unzip <folder_name> - Unzips the given zip file, after accepting the necessary password.
These commands won't be enough to see you through the entire game though! Along the way, you'll need more complicated commands. However, with the help of the hints given in the README files and some Googling, you should be fine.
To begin with, Level 1 has been kept open. Start there.
Good luck!