https://blog.hackster.io/the-reddit-router-scam-9aaf42f349e

A couple of days ago one Reddit user had the misfortune to return home and discover something rather interesting hooked up to their router, placed there by their roommate. A cross between a multi-level marking scam and hardware malware, the malicious board had been put into a position that allowed it to harvest every bit of available data from their local network.

Looking at the picture of the board itself, it appears to be an off-the-shelf Friendly ARM NanoPi NEO single-board computer. Built around an Allwinner H3 processor, a quad-core ARM Cortex-A7 running at 1.2GHz with 256MB of RAM, the board has a 10/100Mbps Ethernet jack, and a micro SD card slot. That’s a specification that provides more than enough horse power to snoop in on any traffic going across the local network.