How to create a brute-force password cracker for alphabetical and alphanumerical passwords?

brute-force, cracking, python, python-3.x

Solution

Here's a naiive brute force method that will guess numbers (`string.digits`) and lower case letters (`string.ascii_lowercase`). You can use `itertools.product` with `repeat` set to the current password length guessed. You can start at `1` character passwords (or whatever your lower bound is) then cap it at a maximum length too. Then just `return` when you find the match.

import itertools
import string

def guess_password(real):
    chars = string.ascii_lowercase + string.digits
    attempts = 0
    for password_length in range(1, 9):
        for guess in itertools.product(chars, repeat=password_length):
            attempts += 1
            guess = ''.join(guess)
            if guess == real:
                return 'password is {}. found in {} guesses.'.format(guess, attempts)
            # uncomment to display attempts, though will be slower
            #print(guess, attempts)

print(guess_password('abc'))

Output

a 1
b 2
c 3
d 4
...
aba 1369
abb 1370
password is abc. found in 1371 guesses.

Problem

I'm trying to create a brute force Python code for alphabetical and alphanumerical combinations and have it report the password and amount of time it took. For numerical combinations I made this: ``` import datetime as dt Password4 = 123456 def crack_password(): start = dt.datetime.now() for n in range(1000000): password_guess = '{0:04d}'.format(n) if password_guess == str(Password4): end = dt.datetime.now() print("Password found: {} in {}".format(password_guess, end - start)) break guesses = crack_password() ``` For alphanumerical combinations (does not work) I tried: ``` import random letters = [str(i) for i in range('a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p')] s = [''.join([a,b,c,d,e,f,g,h]) for a in letters for b in letters for c in letters for d in letters for e in letters for f in letters for g in letters for h in letters] random.shuffle(s) real_password = 'aaaaaaaa' i = 0 for code in s: if code == real_password: print() print('The password is: ', code) break else: i += 1 print(i, ' failures', end='\r') ``` It should report either number of attempts or time it took.

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