How to GPU Accelerate Cracking Passwords with Hashcat

Dec 13, 2011 09:54 PM

How to Crack Passwords Faster by Putting Your GPU to Work with HashcatSecurity on the internet is always changing. Not too long ago, having a 10 character password meant that you were safe from all forms of hash cracking. Hash cracking is when you take a string of characters that have been passed through a cryptographic hash and try to reverse them. The normal processors that are housed inside of our computer cases are general purpose. The processors are not meant for handling complex math and numbers very well, which results in weak hardware when it comes to reversing a complex hash.

With changes in drivers over the past couple of years, it is now possible to crack hashes using your graphics processor, which is far better at math (think of all of the polygons per second your computer has to generate to run a game, that's some serious math!). This means that we all need to increase the length of our passwords for everything if we have not already. This opens up a lot more doors for crackers. Where passwords may have normally been unfeasible to crack, now they can take only a few short hours.

Requirements

Hashcat installed
GPU hardware capable of OpenCL or CUDA
Linux or Windows OS

Create a Hash to Crack

For example, let's make a small length MD5 hash to crack via Mircale Salad's MD5 hash generator.

Make a hash of the word "doggy".
Paste the hash in a notepad, or make sure you do not delete it from your clipboard. We will need it later.

Crack Hash

Follow along with me in this vTutorial as test cracking using my GPU first with bruteforce. After, I demonstrate the performance boost of just one GPU (Hashcat allows up to 16 GPUs).