Bandit: Level 17 - Level 18

Level 17

Username: bandit17
Password: EReVavePLFHtFlFsjn3hyzMlvSuSAcRD

Task:

https://overthewire.org/wargames/bandit/bandit18.html

There are 2 files in the homedirectory: passwords.old and passwords.new. The password for the next level is in passwords.new and is the only line that has been changed between passwords.old and passwords.new

NOTE: if you have solved this level and see ‘Byebye!’ when trying to log into bandit18, this is related to the next level, bandit19 <!-- change username bandit!! --> ### Start

Let’s begin by connecting to the server bandit.labs.overthewire.org and logging in with user bandit17 on port 2220.

We have several commands available for this task:

cat (1)              - concatenate files and print on the standard output
grep (1)             - print lines that match patterns
ls (1)               - list directory contents
diff (1)             - compare files line by line

Solve the level

First we need to choose the correct command here. After checking what the available commands do, diffseems correct here.

Lets check the manual:

DIFF(1)                                                                          User Commands                                                                         DIFF(1)

NAME
       diff - compare files line by line

SYNOPSIS
       diff [OPTION]... FILES

DESCRIPTION
       Compare FILES line by line.

       Mandatory arguments to long options are mandatory for short options too.

Okay in our case we need to check the changes between password.old and password.new

lets try it:

bandit17@bandit:~$ diff passwords.old passwords.new
42c42
< bSrACvJvvBSxEM2SGsV5sn09vc3xgqyp
---
> x2gLTTjFwMOhQ8oWNbMN362QKxfRqGlO

Okay that was quite easy :D - lets try the password, because in the task was written something regarding “bye bye”.

ssh bandit18@bandit.labs.overthewire.org -p 2220

  For support, questions or comments, contact us on discord or IRC.

  Enjoy your stay!

Byebye !
Connection to bandit.labs.overthewire.org closed.

Okay password works, but the connection closes. We will check it in the next level.

Password: x2gLTTjFwMOhQ8oWNbMN362QKxfRqGlO

Explanation:

diff Command

The diff command in Linux compares two files line by line and displays the differences between them. It is commonly used to identify changes between two versions of a file. The output shows lines that need to be added, changed, or removed to make the files identical.

Example Usage:

diff file1.txt file2.txt