Hacking A Xiaomi Air Purifier’s Filter DRM To Extend Its Lifespan

When [Unethical Info] was looking at air purifiers a while back, their eye fell on a Xiaomi 4 Pro, with a purchase quickly made. Fast-forward a while and suddenly the LCD on top of the device was showing a threatening ‘0% filter life remaining’ error message. This was traced back to an NFC (NTAG213) tag stuck to the filter inside the air purifier that had been keeping track of usage and was now apparently the reason why a still rather clean filter was forcibly being rejected. Rather than give into this demand, instead the NFC tag and its contents were explored for a way to convince it otherwise, inkjet cartridge DRM-style.

This is a companion discussion topic for the original entry at https://hackaday.com/2024/01/26/hacking-a-xiaomi-air-purifiers-filter-drm-to-extend-its-lifespan/