How to Build a Credit Card-Size WiFi Deauther

The term “hacking” can mean a lot of different things. Here on Hackster.io, we usually use it to refer to hardware hacking — making electronics do something they weren’t originally intended to. In many people’s minds, however, “hacking” conjures up imagines of people in dark rooms typing away at terminals in order to crack a computer system. That type of hacking can be further divided into either white hat or black hat hacking, which just designates whether it’s ethical or not. If you’re interested in exploring white hat hacking, GioF7 has a tutorial on how to build a useful WiFi deauther.

A WiFi deauther is a device that exploits a weakness in the common 802.11 wireless protocol in order to disconnect any device connected to a particular network. Importantly, the WiFi deauther itself doesn’t have to be connected to that network, because the protocol allows unauthorized devices to send deauthentication messages. That means someone with a WiFi deauther could walk into a location and disconnect everything on the network — including wireless security cameras, computers, and any other device, even if they don’t have the password to connect to the network themselves.

That’s an interesting exploit to experiment with, which is what white hat hacking is all about. To build your own deauther, all you’ll need is a NodeMCU ESP8266 development board, a small OLED display, a USB cable, and a few momentary buttons. As GioF7 illustrates, the circuit to put that all together is very simple, and only requires a handful of connections. Then all you have to do is flash Stefan Kremser’s open-source ESP8266 Deauther 2.0 code, and you can start disconnecting devices from WiFi networks. Or, at least ones where you have permission to do so.