sudo airmon-ng start wlan0 sudo airodump-ng wlan0mon | Problem | Solution | |----------------------------------|-----------------------------------------------| | No interface shown in iwconfig | Plug in a compatible USB Wi-Fi adapter | | Interface exists but Fern fails | Run sudo airmon-ng check kill + manual monitor mode | | Still not working | Use Wifite or aircrack-ng instead of Fern | | Internal card only | Buy a supported external adapter (~$20–40) | Final Note Fern WiFi Cracker is old and less maintained. Many modern Kali users skip it in favor of Wifite (simpler) or aircrack-ng (more control). If you’re learning Wi-Fi penetration testing, focus on those instead.
If you see nothing, your adapter is either not connected or not recognized. NetworkManager and other services can block the interface.
Avoid TP-Link TL-WN722N v2/v3 – they use a different chipset with poor Linux support. 6. Install/update drivers for your adapter If using an RTL88x2AU or RTL8812AU chipset: Kali Linux Fern Wifi Cracker No Wireless Interface Was Found
Now open Fern and try selecting wlan0mon . Fern must be run with root privileges:
sudo apt update sudo apt install realtek-rtl88xxau-dkms Then reboot. sudo airmon-ng start wlan0 sudo airodump-ng wlan0mon |
sudo fern-wifi-cracker Or if using the GUI launcher, make sure it runs as root. If you still get the error, your internal card likely won’t work. Recommended adapters (chipset must be supported):
For other chipsets, check:
ip a Look for wlan0 , wlan1 , or similar.
