Code starts slowing down? MemoryError

[AshkanDev]

(Information before reading: I am a native German speaker and i learned English in school, so i am sorry if something sounds incomprehensible)

Hello there,

i created a brute force program. At first i want to explain how it works. When you start that program, you have to choose a hash algorithm and then put in the hash. Then you have to choose a number for min chars and max chars that the plain password could have. My main problem is that if i choose a password with for example 5 characters and hash that using sha512 or something else and try to brute force that password using my program, the program easily runs through 3 and 4 char passwords, but when it starts to go through all possible 5 char passwords it starts hanging. Normally the progress bar in the console should display how many percent of all possible passwords were tried to compare but it takes very long time to get started with this process.

BTW: If you have any improvements to my code, let me please know because i am learning python and it would be grateful!

Preview (3 min):


Error detected while running:

Error:
Traceback (most recent call last): File "C:/Users/ashka/PycharmProjects/bruteforce/main.py", line 122, in <module> main() File "C:/Users/ashka/PycharmProjects/bruteforce/main.py", line 116, in main bruteforce(min, max, hash, hashfunction) File "C:/Users/ashka/PycharmProjects/bruteforce/main.py", line 91, in bruteforce if bf_sha512(_, hash) is not None: File "C:/Users/ashka/PycharmProjects/bruteforce/main.py", line 23, in bf_sha512 passwords = [functools.reduce(operator.add, (p)) for p in itertools.product(chars, repeat=n)] File "C:/Users/ashka/PycharmProjects/bruteforce/main.py", line 23, in <listcomp> passwords = [functools.reduce(operator.add, (p)) for p in itertools.product(chars, repeat=n)] MemoryError Process finished with exit code 1

Code:

# Just importing modules import itertools import functools import operator import hashlib import time from tqdm import tqdm, trange # Defining the string with all useable characters for a password (excluded special character) chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" # Available hashfunctions hashfunctions = ['sha512', 'sha256', 'md5'] # Function for SHA512 def bf_sha512(n, hash): max_counts = int(chars.__len__())**n print(' ') print('Testing all possible passwords with ' + str(n) + ' characters... [' + str(max_counts) + ']') with tqdm(total=max_counts) as pbar: count = 0 passwords = [functools.reduce(operator.add, (p)) for p in itertools.product(chars, repeat=n)] for password in passwords: count = count + 1 pbar.update(1) if hashlib.sha512(password.encode()).hexdigest() == hash: print('Needed attempts: ' + str(count)) print(' ') print("Hash: " + hash) print("Passwort: " + password) pbar.close() return password pbar.close() return None # Function for SHA256 def bf_sha256(n, hash): max_counts = int(chars.__len__())**n print(' ') print('Testing all possible passwords with ' + str(n) + ' characters... [' + str(max_counts) + ']') with tqdm(total=max_counts) as pbar: count = 0 passwords = [functools.reduce(operator.add, (p)) for p in itertools.product(chars, repeat=n)] for password in passwords: count = count + 1 pbar.update(1) if hashlib.sha256(password.encode()).hexdigest() == hash: print('Needed attempts: ' + str(count)) print(' ') print("Hash: " + hash) print("Passwort: " + password) pbar.close() return password pbar.close() return None # Function for MD5 def bf_md5(n, hash): max_counts = int(chars.__len__())**n print(' ') print('Testing all possible passwords with ' + str(n) + ' characters... [' + str(max_counts) + ']') with tqdm(total=max_counts) as pbar: count = 0 passwords = [functools.reduce(operator.add, (p)) for p in itertools.product(chars, repeat=n)] for password in passwords: count = count + 1 pbar.update(1) if hashlib.md5(password.encode()).hexdigest() == hash: print('Needed attempts: ' + str(count)) print(' ') print("Hash: " + hash) print("Passwort: " + password) pbar.close() return password pbar.close() return None # Function for detecting hash algorithm and choosing the right function to decrypt def bruteforce(min, max, hash, hashfunction): print('Working... Do not exit!') print(' ') starttime = time.time() max_counts = int(chars.__len__())**int(max) print(f'Max possible password combinations: {max_counts:,d}') for _ in range(int(min), int(max) + 1): if hashfunction == 'sha512': if bf_sha512(_, hash) is not None: break elif hashfunction == 'sha256': if bf_sha256(_, hash) is not None: break elif hashfunction == 'md5': if bf_md5(_, hash) is not None: break endtime = time.time() executiontime = endtime - starttime print("Execution Time: " + str(executiontime) + " sec") # Main function def main(): print("Python Bruteforce v1.0") print(' ') print('Used pattern: ' + chars) print('Hashfunctions: sha512, sha256, md5') hashfunction = input('Hashfunction: ') if hashfunction in hashfunctions: hash = input('Enter ' + hashfunction + ' hash: ') min = input('Enter min password length: ') max = input('Enter max password length: ') print(' ') bruteforce(min, max, hash, hashfunction) else: print('Please select an given hashfunction!') if __name__ == '__main__': main()

[AshkanDev]

Problem solved!

For those who get the same error, here is the answer:
the problem in the line that causes this error is the transformation from a generator (a piece of code that yields one result at a time until it finishes running) that is very memory-efficient, to a list by using [] around

functools.reduce(operator.add, p) for p in itertools.product(chars, repeat=n)

.
by converting it into a list you make the generator output all its values into a list, which cannot contain more than 536,870,912 items on 32bit machines. when the list gets bigger than that you get the memory error.

solution: remove the []