In the field of computer security, cryptography holds the main space. In the study of cryptography, we come across many types of algorithms but we can broadly divide the encryption ciphers into two categories – two way algorithms and one way algorithm. The two way algorithms allow the encryption of the source message as well as decryption of the encrypted message back into its un-encrypted format. Then there are one way algorithms that are used only to encrypt the message into encrypted format – the decryption is not possible by design.
These one way encryption algorithms are often used to calculate the hashes of the source message which is unique to the original message. These algorithms include MD4, MD5, RIPEMD, SHA-1, SHA-256, SHA-512, and many more. Of all of these, MD5 has been known to show weakness as they can be cracked using the powerful computers of today. In fact there are many programs available online that can attempt a bruteforce attack on the MD5 hashes in order to determine the original message.
Only bruteforce method is going to work against ciphers like MD5 as the hashes cannot be decrypted back into the source message. There is a program called MD5 Bruteforcer that can use the CUDA API available in the graphics processor of some graphics cards. If you do not know whether your GPU supports CUDA, you can use the GPU-Z and it will show you all the capabilities of the graphics card.
MD5 Bruteforcer is a small command line interface (CLI) program. We can launch by double-clicking on it and then enter some of the values that it asks for. For example, we have to enter the MD5 hash value that you want to work on. You have to enter the number of characters and the source message length etc.
MD5 Bruteforcer will use the GPU to generate all the hashes and check whether it has created a matching hash. This is much faster if your have a really powerful GPU. It may find the source message instantly for very small messages but take many days for longer messages.
MD5 Bruteforcer is an easy way to demonstrate the vulnerability of the MD5 algorithms. This is why nobody uses MD5 for any thing of serious nature. Similarly, DES and RC2 are also considered weak.
You can download MD5 Bruteforcer from https://github.com/erickutcher/md5bruteforcer.