Hash Kit Professional: Dictionary attack and bruteforce user manual (Release date 5 May 2014)

Dictionary attack & Bruteforce
Manual version: 5 May 2014

Introduction

User Interface

Pre-image resistant For any given Y, it is difficult to find an X such that H(X)=Y.

In here given Y, which means hash value, we try to find X. By using [Dictionary attack & Brute-force]

There are six parts in Dictionary attack and Brute force

1. Configuration

We have four type attack in the configuration:

l Dictionary attacks:

A dictionary file might contain words, we try to find H(word) == Y, if H(word) = Y, the word is X.

[Default dictionary] User can choose the default dictionary. The default dictionary is come from Ubuntu system.

[Customize dictionary] User can choose a customize dictionary, the dictionary format is *.txt

l Search attacks:

Random string instead of a list of dictionary file, random string characters include number 0~9, English letters a~z or A~Z, other symbols like %*$..., covers all possible combinations of a character set, but password length is fixed by user.

[Charset] The random message character option

[Message length] The message length choose from minimal length to maximal length. In this section, minimal length is less than or equal to the maximal length

[Number of generation] The maximal time for the string generator

l Rule-based search attacks

If user know a part of fragment of X, and ((fragment of X) + random string) as key word, try to find the whole value X

[Charset] The random message character option, it is the same as search attack

[Length of string text] The length of message text is fixed, not like the search attacks, it is role-based.

[String fragment] The fragment of message. For example, the whole message is “apple”, so “app” is a fragment of message

[Fragment position] There are two option, [fragment put first] and [fragment put last], for example, the whole message is “apple1991”, we know fragment “app” at the beginning of the message, so the fragment need to put first. Otherwise, if we know the fragment is a year “1991” at the end of the message, so we can choose fragment put last.

l Brute-force attacks

Try all possible combinations (no selection by user), the password length is not fixed, a range of password length can be setup by user. Actually it is similar as search attacks, but the random range is much bigger than search attacks. It might take long time to run because of the large number of possible combinations.

2. Hash format

Hash format is an option to choose hash function. MD5 and SHA1 are two option for user easier to test. The advance option which is customized algorithm, user can choose external hash function, the external hash function format is *.exe

3. Hash value

Hash value section is for user inputting hash value for analyzing. The hash value must base on Hex.

The bit size is for select a part of hash value. For example, the hash value “1f3870be274f6c49b3e31a0c6728957f”, if user choose 36 bits, the hash value could be “1f3870be2”. If user choose whole bit size, so the analyzer will analyze all the bit from the user input.