Wireless capturing

1. Goal

   • Capture, analyze and decrypt wireless traffic.

2. Used hardware

   • Alfa AWUS036NHA (Long-range USB Adapter)
   • 1 laptop with Kali Linux

3. Used software

   • Kali Linux (2020.1)

4. Setup

5. Getting started

   1. Display the list of available adapters. (Kali Linux)

   kali@kali:~# sudo airmon-ng
   
   PHY	Interface	Driver		Chipset
   
   phy0	wlan0		iwlwifi		Intel Corporation Centrino Advanced-N 6205 [Taylor Peak] (rev 34)
   phy1	wlan1		ath9k_htc	Qualcomm Atheros Communications AR9271 802.11n
   
   kali@kali:~#
   

   2. Monitor mode allows a wireless network interface controller to monitor all traffic received on a wireless channel.

      1. Kill the network managers. (To Avoid interference with other tools)

      kali@kali:~# sudo airmon-ng check kill
      
      Killing these processes:
      
      PID Name
      643 wpa_supplicant
      
      kali@kali:~#
      

      2. Put the adapter in monitor mode.

      kali@kali:~# sudo airmon-ng start wlan1
      
      PHY	Interface	Driver		Chipset
      
      phy0	wlan0		iwlwifi		Intel Corporation Centrino Advanced-N 6205 [Taylor Peak] (rev 34)
      phy1	wlan1		ath9k_htc	Qualcomm Atheros Communications AR9271 802.11n
      
                      (mac80211 monitor mode vif enabled for [phy1]wlan1 on [phy1]wlan1mon)
                      (mac80211 station mode vif disabled for [phy1]wlan1)
      
      kali@kali:~#
      
      

   3. Start Wireshark and select the wlan1mon interface.

   kali@kali:~# sudo wireshark 
   

   

   4. Check the result.

   

   5. Decrypt wireless traffic in Wireshark.

      1. Go to Edit -> Preferences -> Protocols -> IEEE 802.11.

      2. Click on the "Edit..." button next to "Decryption Keys" to add keys.

      3. Check the decrypted wireless traffic More information about decrypting IEEE 802.11 (opens new window)

6. Conclusion

   • It is perfectly possible to capture wireless networks cheaply.