This Little Piggy Audits Your Wi-Fi Security

How secure are the wireless networks at your home or place of business? You can update the firmware of your networking devices and configure their settings according to the generally accepted best practices, but you won’t really know the answer to this question until you do some probing. The best way to do this is to grab the same types of tools used by malicious hackers and let them loose on your own equipment to determine what they can reveal.

Using a new open source and inexpensive device created by Midwest Gadgets would be a great way to get started. Powered by an ESP32-C5 microcontroller, this device, called Piglet, will scan and test any wireless networks within range. The information it provides can be used to harden your network against any potential future attackers.

Piglet is built around accessible hardware like the Seeed Studio XIAO ESP32C5 development board. This board was selected specifically because it supports dual-band Wi-Fi scanning, allowing the device to detect both 2.4 GHz and 5 GHz wireless networks. Combined with an external antenna connected through an SMA to U.FL adapter, Piglet can capture signals from a wide range of nearby routers and access points.

To make the device practical for field use, Piglet integrates several additional components onto a custom printed circuit board. A small 0.97-inch OLED display based on the SSD1306 controller provides real-time feedback about detected networks and device status. A MicroSD card module stores collected data for later analysis, while a compact tactile button allows the user to control scanning functions.

Location data is also important when scanning larger areas. For this reason, the build incorporates an ATGM336H GPS module, which records the coordinates of each detected wireless network. This allows users to create detailed maps of network coverage or contribute their findings to online databases.

Assembly of the device is straightforward for anyone with basic soldering skills. The ESP32C5 module is mounted onto the custom PCB, followed by the SD card module, the OLED display headers, and the GPS unit. Builders can optionally attach a 3.7-volt lithium-polymer battery directly to pads on the back of the board, creating a fully portable scanner that can run independently while on the go.

Once the hardware is assembled, the final step is loading the open source firmware. Using a flashing tool and the project’s bootloader and binary files, the firmware can be uploaded to the microcontroller in just a few minutes. A configuration file placed on the SD card allows users to add Wi-Fi credentials, specify the board type, and enter an API token for automatic data uploads to public databases.

With its low cost, open hardware design, and simple construction, Piglet offers an accessible entry point for anyone interested in wireless security research or community network mapping. Further details are available on GitHub.