Post

OverTheWire: Bandit Level 10 → Level 11

OverTheWire - Bandit

Level Goal

The password for the next level is stored in the file data.txt, which contains base64 encoded data

Commands you may need to solve this level

grep, sort, uniq, strings, base64, tr, tar, gzip, bzip2, xxd

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
> whatis grep  
grep (1)             - print lines that match patterns

> whatis sort  
sort (1)             - sort lines of text files

> whatis uniq  
uniq (1)             - report or omit repeated lines

> whatis strings  
strings (1)          - print the sequences of printable characters in files

> whatis base64  
base64 (1)           - base64 encode/decode data and print to standard output

> whatis tr  
tr (1)               - translate or delete characters

> whatis tar  
tar (1)              - an archiving utility

> whatis gzip  
gzip (1)             - compress or expand files

> whatis bzip2  
bzip2 (1)            - a block-sorting file compressor, v1.0.8

> whatis xxd  
xxd (1)              - make a hexdump or do the reverse.

Note: All commands don’t have to be used to complete level

Helpful Reading Material

Base64 - Wikipedia

Bash base64 encoding and decoding

Solution

View the contents of the current working directory

1
2
bandit10@bandit:~$ ls  
data.txt

View the data that is present in the file

1
2
bandit10@bandit:~$ cat data.txt  
VGhlIHBhc3N3b3JkIGlzIElGdWt3S0dzRlc4TU9xM0lSRnFyeEUxaHhUTkViVVBSCg==

Looking at the content it looks like a string of random characters but from the question we know that the data is base64 encoded. We can decode this data using the base64 command that is present on Unix systems. The -d flag is used to decode the data

(For detailed information on base64 encoding refer to the attached article)

1
2
bandit10@bandit:~$ cat data.txt | base64 -d  
The password is IFukwKGsFW8MOq3IRFqrxE1hxTNEbUPR

We have found the password for the next level !!

Logout of the current session and use the password of user bandit11 to access the next level

1
2
3
4
> ssh bandit11@bandit.labs.overthewire.org -p 2220  
This is a OverTheWire game server. More information on http://www.overthewire.org/wargames

bandit11@bandit.labs.overthewire.org's password: IFukwKGsFW8MOq3IRFqrxE1hxTNEbUPR
This post is licensed under CC BY 4.0 by the author.