Learn linux command by playing Bandit wargame. The Bandit wargame is aimed at absolute beginners. It will teach the basics needed to be able to play other wargames. Below is the solution of Level 12 → Level 13.
In this post we will learn about various compression techniques and
how to decompress file. We will learn how to convert binary to hex file
and vice-versa.

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Bandit Level 0 to Level 3
Bandit Level 4 to Level 8
Bandit Level 9 to Level 11

Level Goal

The password for the next level is stored in the file data.txt, which is a hexdump of a file that has been repeatedly compressed. For this level it may be useful to create a directory under /tmp in which you can work using mkdir. For example: mkdir /tmp/myname123. Then copy the datafile using cp, and rename it using mv (read the manpages!)

Commands you may need to solve this level

grep, sort, uniq, strings, base64, tr, tar, gzip, bzip2, xxd, mkdir, cp, mv, file

Solution :


Command to connect remote host : 
ssh [email protected] -p 2220
password is 
5Te8Y4drgCRfCx8ugdwuEX8KFC6k2EUu
As mentioned in question make a new directory in /tmp and rename the file.
xxd
program is used to make a hexdump or to do the reverse. Option 
-r
convert hexdump into the binary. File 
myfile.txt
is a hexdump and convert it into a binary file 
myfile1.bin
using command
xxd -r myfile.txt > myfile1.bin
Using command 
file myfile1.bin
, we found that 
myfile1.bin
is a gzip compressed data.
zcat
is a program supplied with 
gzip
and is used to decompress gzip compressed files.
zcat myfile1.bin > myfile2
Again using 
file
command on 
myfile2
, we found that it is bzip2 compressed data.
bzcat
program is supplied with 
bzip2
and is used to decompress bzip2 compressed files.
bzcat myfile2 > myfile3
myfile3
is gzip compressed file so use 
zcat
program to decompress it in 
myfile4
. 
myfile4
is a POSIX tar archive.
tar
program is used for archiving file and options 
x
is used to extract an archive, 
f
is used to specify name of the tar archive and 
v
is used for more detailed listing.
tar -xvf myfile4
This command outputs file 
data5.bin
which is again a tar archive. Again use 
tar
program on 
data5.bin
which outputs 
data6.bin
. 
data6.bin
is a bzip2 compressed file and use 
bzcat
program to decompress it to 
myfile7
.
myfile7
is a tar archive and use 
tar
program which outputs 
data8.bin
. 
data8.bin
is a gzip compressed file and use 
zcat
to decompress it to file 
myfile9
.
myfile9
contains ASCII text and 
cat myfile9
tells the password for the next level.
The password for the next level is 
8ZjyCRiBWFYkneahHwxCv3wb2a1ORpYL
.
Reference : The Linux Command Line – A Complete Introduction
https://linux.die.net/man/1/xxd


Next Post

Bandit Level 13 to Level 15
Bandit Level 16 to Level 18
Bandit Level 19 to Level 20
Bandit Level 21 to Level 22
Bandit Level 23 → Level 24
Bandit Level 24 → Level 25
Bandit Level 25 to Level 26
Bandit Level 27 to Level 31
Bandit Level 32 → Level 33
Originally posted at Programmercave


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