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Question

When I started to recover the wifi key using reaver 1.4, after writing the command

root@kunjesh-Ideapad-Z570:~/reaver-1.4/src# reaver -i mon0 -b <USSID>

it is giving the error

Reaver v1.4 WiFi Protected Setup Attack Tool
Copyright (c) 2011, Tactical Network Solutions, Craig Heffner <cheffner@tacnetsol.com>
[-] Failed to initialize interface 'mon0'
[-] Failed to recover WPA key

kindly help me.

Answer

Make sure you have created the directory /etc/reaver; otherwise things won't work.

Run sudo airmon-ng start <INTERFACE>.

Check that iwconfig shows the new interface (usually mon0) as being in Monitor mode. Managed will not work.

Run aircheck-ng and turn off any processes it tells you might be bad. Afterwards, use airmon-ng stop mon0 and then airmon-ng start wlan0 to recreate the (hopefully) monitoring interface.