OverTheWire: Leviathan Level 3
We can get started with the third level of Leviathan by connecting to the remote machine with SSH. If you haven’t gotten the password, you can read my walkthrough of the last level.
Username: leviathan2
Password: ougahZi8Ta
When we use the ls command to list all the files in the home directory.
We see there is another executable file that we can run. So let’s do just that.
And the file has given us a usage message, telling us that we need to run the executable with a filename as an argument. We notice that in the ls command, it gives us the name of the user who owns the file as leviathan3. So we can try and aim the executable at the leviathan3 password file to see if it will print out the next levels password.
And it says that we don’t have access to that file. So we need to come up with a solution that will enable us to print out the password in the password file.
To do this, we need to use a very clever trick with the link command and escape characters.
Firstly, we need to create a new directory in the tmp/ folder and create a file that contains a space in its filename.
And now what we can do, is use the ln command, which can be used to create links between files. If you haven’t heard of this before, here is an article you can read which talks through links. https://www.linux.com/topic/desktop/understanding-linux-links/
The type of link we want to create is a symbolic link, but we are only going to link it to a non-existent file called pass. This is so when we run the printfile command, it will first check and print out the symbolic link file, before checking to see if it exists since we are entering in a valid filename.
So that will look like the following.
So it prints out the password of the symbolic link before actually checking if the file exists as we didn’t create a file called pass.
So the next levels password is Ahdiemoo1j
To continue, please read my Leviathan 4 walkthrough. Level 4
Thank you for reading. 