Encryption of 40-bit MD5 and 48-bit MD5

Compared with 32-bit MD5.asp and 40-bit MD5.asp files,

The 40-bit encryption can be used to find out the rule. We can also use the 48-bit encryption.

First look at the 32-bit encryption:

MD5 = LCase (WordToHex (a) & WordToHex (B) & WordToHex (c) & WordToHex (d ))

Let's look at the 40-bit encryption:

MD5 = LCase (WordToHex (c) & WordToHex (a) & WordToHex (B) & WordToHex (c) & WordToHex (d ))

32-bit encryption uses & connects 4 variables, 40-bit encryption uses & connects 5 variables,

In this way, each variable occupies eight seats in the encrypted ciphertext,

Therefore, you only need to remove the first eight digits in the attack,

However, this is only a method to crack this encryption,

We can also perform other 40-bit MD5 encryption methods,

For example:

MD5 = LCase (WordToHex (a) & WordToHex (B) & WordToHex (c) & WordToHex (d) WordToHex (c )),

Here I moved the WordToHex (c) variable to the back,

In this case, we need to remove the last 8 bits to run the MD5 command when we crack it again,

You can obtain other results by putting them in the middle or doubling them,

But the premise is that we must know the laws of the connected variables,

That is, you read the 40-bit encrypted MD5.asp file.

Let's take a look at the differences between 40-bit MD5 encryption and 32-bit encryption:

32-bit admin encryption: 21232f297a57a5a743894a0e4a801fc3

40-bit admin encryption: 43894a0e21232f297a57a5a743894a0e4a801fc3

You can compare whether the first 8 bits in the 40-bit encryption are the WordToHex (c) variable in the 32-bit encryption,

Similarly, if we add a WordToHex (c) before the 40-bit MD5 encryption ),

The encrypted result is 48-bit encryption.