Introduction
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If you’re just getting started with Linux, cybersecurity, or Capture The Flag (CTF) challenges, the Bandit wargame from OverTheWire is one of the best hands-on introductions you can find. Designed specifically for beginners, Bandit walks you through the fundamentals of the Linux command line while subtly building the mindset needed for penetration testing and security research.

In this post, we’ll walk through Levels 0–4, breaking down not only how to solve them, but also why each command works.

Level 0 -> 1
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Level Goal

The password for the next level is stored in a file called readme located in the home directory. Use this password to log into bandit1 using SSH. Whenever you find a password for a level, use SSH (on port 2220) to log into that level and continue the game.

Solution

Connect to the server as bandit0:

[greycipher@remnant ~]$ ssh [email protected] -p 2220

Once inside, list the directory and read the file:

bandit0@bandit:~$ ls
readme

bandit0@bandit:~$ cat readme
Congratulations on your first steps into the bandit game!!
Please make sure you have read the rules at [...]

The password you are looking for is: [REDACTED]

Notes

cat reads the contents of a file and prints it to standard output.
ls lists the files in the current directory.

These are the two most basic commands you will use throughout this series.

Level 1 -> 2
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Level Goal

The password for the next level is stored in a file called - located in the home directory.

Solution

Connect to the server using the password previously acquired and the username bandit1:

[greycipher@remnant ~]$ ssh [email protected] -p 2220

From here list the directory and read the content of the target file:

bandit1@bandit:~$ ls
-

bandit1@bandit:~$ cat ./-
[REDACTED]

Notes

Files starting with - are treated as flags. Use ./ to reference them as a path.

Level 2 -> 3
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Level Goal

The password for the next level is stored in a file called –spaces in this filename– located in the home directory.

Solution

Using the username bandit2 and the password from the previous level connect to the server:

[greycipher@remnant ~]$ ssh [email protected] -p 2220

Read the content of the file by either using quotes "" or by referencing it as a path.

bandit2@bandit:~$ ls
--spaces in this filename--

bandit2@bandit:~$ cat ./--spaces\ in\ this\ filename--
[REDACTED]

Notes

Filenames with spaces need to be quoted or escaped. Either wrap the whole name in quotes or use a backslash before each space: cat spaces\ in\ this\ filename.

Level 3 -> 4
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Level Goal

The password for the next level is stored in a hidden file in the inhere directory.

Solution

Use the username bandit3 and the password from the previous level to connect to the server:

[greycipher@remnant ~]$ ssh [email protected] -p 2220

Once connected start looking around for the hidden files using the commands we already know.

bandit3@bandit:~$ ls
inhere

bandit3@bandit:~$ cd inhere

bandit4@bandit:~/inhere$ ls -a
.  ..  ...Hiding-From-You

bandit3@bandit:~/inhere$ cat ...Hiding-From-You
[REDACTED]

Notes

Hidden files on Linux start with a dot. ls skips them by default, use ls -a to show all files including hidden ones.

Level 4 -> 5
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Level Goal

The password for the next level is stored in the only human-readable file in the inhere directory. Tip: if your terminal is messed up, try the “reset” command.

Solution

With the username bandit4 and the acquired password connect to the server:

[greycipher@remnant ~]$ ssh [email protected] -p 2220

Once inside we can see there are different files in the folders and checking every file by hand can be very slow, but knowing that the file we’re looking for is the only one which is also human-readable we can use the file command to check the type of data contained in a file.

bandit4@bandit:~$ cd inhere/

bandit4@bandit:~/inhere$ ls
-file00  -file01  -file02  -file03  -file04  -file05  -file06  -file07  -file08  -file09

bandit4@bandit:~/inhere$ file ./*
./-file00: data
./-file01: OpenPGP Public Key
./-file02: OpenPGP Public Key
./-file03: data
./-file04: data
./-file05: data
./-file06: data
./-file07: ASCII text
./-file08: data
./-file09: data

bandit4@bandit:~/inhere$ cat ./-file07
[REDACTED]