OverTheWire Wargames

Bandit Level 12 –> Level 13

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

ls command show file in home directory “data.txt” contain hexdump

bandit12@bandit:~$ ls
data.txt

Make “banlev12” dir in tmp folder then copy data.txt to it

bandit12@bandit:~$ mkdir /tmp/banlev12
bandit12@bandit:~$ cp data.txt /tmp/banlev12
bandit12@bandit:~$ cd /tmp/banlev12
bandit12@bandit:/tmp/banlev12$

Using file command we see that it is ASCII file so we need to convert to binary form in new file

bandit12@bandit:/tmp/banlev12$ file data.txt
data.txt: ASCII text
bandit12@bandit:/tmp/banlev12$ xxd -r data.txt newdata

Again use file command implies that newdata file is gzip commpressed data

bandit12@bandit:/tmp/banlev12$ file newdata
newdata: gzip compressed data, was "data2.bin", last modified: Thu May  7 18:14:30 2020, max compression, from Unix

Lets add .gz file extension and decompress it, that produce newdata file

bandit12@bandit:/tmp/banlev12$ mv newdata.gzip newdata.gz
bandit12@bandit:/tmp/banlev12$ gzip -d newdata.gz
bandit12@bandit:/tmp/banlev12$ ls
data.txt  newdata

Again use file command implies that newdata file is bzip2 commpressed data

bandit12@bandit:/tmp/banlev12$ file newdata
newdata: bzip2 compressed data, block size = 900k

Lets add .bz2 file extension and decompress it, that produce newdata file

bandit12@bandit:/tmp/banlev12$ mv newdata newdata.bz2
bandit12@bandit:/tmp/banlev12$ bzip2 -d newdata.bz2
bandit12@bandit:/tmp/banlev12$ ls
data.txt  newdata

Again use file command implies that newdata file is gzip commpressed data

bandit12@bandit:/tmp/banlev12$ file newdata
newdata: gzip compressed data, was "data4.bin", last modified: Thu May  7 18:14:30 2020, max compression, from Unix

Add .gz file extension and decompress it, that produce newdata file

bandit12@bandit:/tmp/banlev12$ mv newdata newdata.gz
bandit12@bandit:/tmp/banlev12$ gzip -d newdata.gz
bandit12@bandit:/tmp/banlev12$ ls
data.txt  newdata

Again use file command implies that newdata file is tar archive

bandit12@bandit:/tmp/banlev12$ file newdata
newdata: POSIX tar archive (GNU)

Add .tar file extension and decompress it, that produce data5.bin file

bandit12@bandit:/tmp/banlev12$ mv newdata newdata.tar
bandit12@bandit:/tmp/banlev12$ tar -xvf newdata.tar
data5.bin

Again use file command implies that data5.bin file is tar archive and decompress it

bandit12@bandit:/tmp/banlev12$ file data5.bin
data5.bin: POSIX tar archive (GNU)
bandit12@bandit:/tmp/banlev12$ tar -xvf data5.bin
data6.bin

data6.bin file is tar archive, decompress it

bandit12@bandit:/tmp/banlev12$ file data6.bin
data6.bin: bzip2 compressed data, block size = 900k
bandit12@bandit:/tmp/banlev12$ mv data6.bin data.bz2
bandit12@bandit:/tmp/banlev12$ bzip2 -d data.bz2
bandit12@bandit:/tmp/banlev12$ ls
data  data5.bin  data.txt  newdata.tar

Do that until you reach to password

bandit12@bandit:/tmp/banlev12$ file data
data: POSIX tar archive (GNU)
bandit12@bandit:/tmp/banlev12$ tar -xvf data
data8.bin
bandit12@bandit:/tmp/banlev12$ file data8.bin
data8.bin: gzip compressed data, was "data9.bin", last modified: Thu May  7 18:14:30 2020, max compression, from Unix
bandit12@bandit:/tmp/banlev12$ mv data8.bin data9.gz
bandit12@bandit:/tmp/banlev12$ gzip -d data9.gz
bandit12@bandit:/tmp/banlev12$ ls
data  data5.bin  data9  data.txt  newdata.tar
bandit12@bandit:/tmp/banlev12$ file data9
data9: ASCII text
bandit12@bandit:/tmp/banlev12$ cat data9
The password is 8ZjyCRiBWFYkneahHwxCv3wb2a1ORpYL

Password

8ZjyCRiBWFYkneahHwxCv3wb2a1ORpYL

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