cRARk 5.1

Fastest freeware utility to crack RAR password

New 64-bit version! cRARk for 7-Zip released!



User's opinions

GUI & distributed RAR password recovery

cRARk for 7-Zip

 1996, cRARk 1.0 - just first RAR cracker
 2006, cRARk 3.0 - fastest recovery of RAR 3.0 passwords
 2009, cRARk 3.2 - world's first CUDA-aware RAR password recovery
 2011, cRARk 3.4 - world's first OpenCL-aware RAR password recovery
 2011, cRARk 5.0 - world's first RAR 5.0 password recovery
  Designed for NVidia CUDA Designed for OpenCL

cRARk purpose

The primary goal of cRARk is to
  • recover your forgotten password on RAR archives.
    Rar/WinRar versions 2.x-5.x up to 5.0 are supported.
Please bear in mind you have quite no chance to crack unknown password (longer than 6-7 symbols) if you have no additional info about it.
cRARk is the tool for professionals, it uses command-line interface, has no GUI.
cRARk is the freeware utility for Win32/64, Linux, Mac OS.

Features and limitations

Advantages of cRARk are:
  • Absolutely free
  • All RAR versions support, including the latest RAR 5.0
  • One of the fastest RAR password recovery software, with the optimization for latest x86 instructions: AVX2, AVX, XOP, AES-NI for Intel Haswell and AMD Bulldozer processors
  • Support of GPU password recovery on NVIDIA (including Maxwell) and AMD GPUs using CUDA and OpenCL technologies
  • Multi-volume, self-extracting, encrypted header archives support
  • Unique PCL language which is extremely efficient if user remembers any information about a forgotten password
  • Portability (Windows, Linux, Mac OS versions are available)

Limitations of cRARk (comparing to Parallel Password Recovery):
  • No GUI, pause/resume feature etc
  • No multi-core support, only one CPU or GPU is used
  • Password length is limited to 28 symbols

RAR security overview

RAR/WinRAR archiver version 2.x used its proprietary, but rather strong encryption algorithm. At least no RAR 2.0 attacks were known except brute force for password recovery.
Starting from version 3.0, RAR has been using a strong AES algorithm, which also doesn't allow any attacks more effective than the brute force. Besides, the key derivation function uses more than 70000 SHA-1 transformations and brute force rate on modern CPU is very low, only several hundreds of passwords per second.
RAR 5.0 encryption is quite the same, using PBKDF2 key derivation with SHA-256 hash and the rate is even slower (in 25-100% on different hardware comparing to RAR 3.0). This carries inference that RAR password encryption is one of the strongest between popular encryption systems in the context of brute force rate.

  cRARk download

You need RAR 5.0 to unpack these files!



32-bit (not supported)

Windows      NEW cRARk v. 5.1 with CUDA support, Win64 - recommended for NVIDIA GPU
cRARk v. 5.1 with OpenCL support, Win64 - recommended for AMD GPU
cRARk v. 5.0c with CUDA support, Win32/Win64
cRARk v. 5.0c with OpenCL support, Win32/Win64
This is the last version supporting Windows XP and NVIDIA G80 cards! Will not be updated!

Linux NEW cRARk v. 5.1 with CUDA support, binaries
cRARk v. 5.1 with OpenCL support, binaries
cRARk v. 3.43 with CUDA support, binaries, kernel 2.6.24
cRARk v. 3.43 with OpenCL support, binaries, kernel 2.6.24
cRARk v. 3.41 with no GPU support, binaries, static, 700K

Mac OS X cRARk v. 3.43 with CUDA support recommended for NVIDIA GPU
cRARk v. 3.43 with OpenCL support recommended for AMD GPU and no GPU

Crark GUI wrapper for Windows (900K)
I'm not an auhtor of this software, I'm not liable for any its using. Please contact directly the author if you find any bugs
Customer's FAQ

  • 0. What is the password for the achive?

    There is no password to the crark's executables and configuration files.

  • 1. How to break and then to continue the search.

    The program may be broken painlessly once the message "Testing XX-chars passwords..." is displayed, and then the search may be continued with -lXX option.

  • 2. How to resume search from the password XXX?

    Sorry, no way. I's implemented in the PCL 3.0 used in Parallel Password Recovery.

  • 3. The program has been searching for 10 days, but my password is not yet at hand.

    Alas! It can't be helped. May be your password is too long, or the search set is wrong. Additional information on the password is necessary.

  • 4. I have tested your program. To my mind, your program is nothing but utter error, it cannot even find "aaa2"-like password.

    File password.def (from the distributed archive) searches through only lower-cased Latin letters. Change your password definition to "[$a $1] *" and everything will be ok.

  • 6. I've got beginning of one file from archive in plain text. Will it be useful to me?

    No. At least, I couldn't use it. Could you? RAR encryption sources are available in WinRAR distribution.

  • 7. I'd like to optimize your program. How can I get the sources?

    You don't need them. Take UnRar sources and optimize the SetCryptKeys() function. Next contact me.

  • 8. I need GUI, multicore support, pause/resume etc.

    cRARk is the free program, and I have no time to support such features. To find all you need, please look at GUI, multicore RAR Password Recovery which licensed cRARk and PCL engine.

More questions and answers you'll find in the included documentation.
About CUDA/OpenCL support
  • 1. Which GPU is supported by cRARk?

    You need NVIDIA GPU card with CUDA support with compute capability 1.1 or higher; or AMD Radeon GPU card 5000/6000/7000 series; or Intel HD Graphics 4000 and higher with OpenCL support. Here is the list of such a cards with the exception of GeForce 8800 GTX/GTS, which has capability 1.0 You also need the latest drivers with CUDA support for NVIDIA cards:
    CUDA-capable drivers
    Notebook drives or
    latest drivers with OpenCL support for AMD Radeon cards:
    OpenCL-capable drivers

  • 2. How to run crark on 64 bit OS?

    On Win64 it runs fine.
    On Linux amd64 apart from CUDA drivers and CUDA shared libraries, you should install the ia32-libs package.
    Under Mac OS you may need to boot in 32-bit mode.

  • 3. I've got an error like "cudaThreadSynchronize failed: launch exceeded timeout"
    or "Display driver stopped and has recovered".

    a. If you're using Windows Vista/7, please read the article. Or simply run the file driver-timeout.reg from the cRARk's archive and reboot.
    b. Try to use the recommended -d option (look at the program output).
    c. Don't run crark on primary graphics card, use separate GPUs for crark and monitor.

  • 4. Program hangs after printing "Trying to compile XXXX kernel".

    Please install the latest OpenCL drivers..

  • 5. I've got any error in CUDA/OpenCL or CUDA/OpenCL is not working at all.

    Please install the latest drivers (see above).. Don't overclock neither GPU nor CPU!
    If this not helps, please install the fresh copy of your operating system and install the drivers.

  • 6. I'd like to optimize your CUDA code. How can I get the source?

    Here it is. If you reach better speed, please contact me.

PCL Language

A good online descripion of PDL language, which is 95% compatible with PCL, you may find here.
  Last updated: 25 Jul 2015 © Pavel Semjanov, 2000-15