If you forget your password for compressed archive (rar, 7z, zip), this program is the solution.This program uses bruteforce algorithm to find correct password. You can specify wich characters will be used in password generations.

Warning: Please don’t use this program for any illegal things!

Preparing your system

First you need to install the following package

#apt-get install libxml2-dev build-essential

Now you need to download the latest version of rarcrack from here

#wget http://surfnet.dl.sourceforge.net/sourceforge/rarcrack/rarcrack-0.2.tar.bz2

Now you have rarcrack-0.2.tar.bz2 file and you need to extract this file

#tar -xjf rarcrack-0.2.tar.bz2

#cd rarcrack-0.2

#make

You must be root to run the following command

#make install

Using Rarcrack

rarcrack your_encrypted_archive.ext [–threads thread_num] [–type rar|zip|7z]

Example

rarcrack something.rar

After the cracking started RarCrack will print the current status of cracking and save it’s to a status file. If you want more specific password character set, you need to run RarCrack to create the XML status file (3 sec).

Coba eksekusi.
Dengan password sederhana, cuma 2 karakter “1i”. Disini prosesnya hanya 1 menit (singkat).
x# rarcrack Howto_Paswd_1i.rar –type rar RarCrack! 0.2 by David Zoltan Kedves (kedazo@gmail.com)

INFO: the specified archive type: rar
INFO: cracking Howto_Paswd_1i.rar, status file: Howto_Paswd_1i.rar.xml
GOOD: password cracked: ‘1i’
#

Untuk yang ini dengan password yang agak panjang, passwordnya 6 karakter “paswd1” atau kondisi ini dapat di katakan tidak tahu passwordnya apa dan berapa karakter, jadi dalam test cracking saya masukan sampai 8 karakter. Karena prosesnya membutuhkan waktu lama, maka di stop ajah, jadi disini sudah mengalami pemotong proses, tapi ininya dapat di lihat proses cracking

# rarcrack Howto_paswd1.pdf.rar –threads 8 –type rar
RarCrack! 0.2 by David Zoltan Kedves (kedazo@gmail.com)

INFO: the specified archive type: rar
INFO: cracking Howto_paswd1.pdf.rar, status file: Howto_paswd1.pdf.rar.xml
Probing: ‘1B’ [51 pwds/sec]
Probing: ’45’ [51 pwds/sec]
Probing: ‘6u’ [49 pwds/sec]
Probing: ’00a’ [48 pwds/sec]
Probing: ’02c’ [42 pwds/sec]
Probing: ‘048’ [40 pwds/sec]
dst……

Sumber: Howto Crack Rar, 7z, and zip files in Linux