A new Philips Sonicare toothbrush not only reminds you when it’s time to switch brush heads, but also communicates with a handle and can be hacked. The toothbrush interacts with the insertion of a new brush head through an LED. A recent blog post details how the NFC technology in the brush head, which is connected to an antenna and an integrated circuit, functions. The toothbrush saves the brush head’s usage time in Hexadecimal code and will blink an LED when it’s time to replace it. The brush head is protected by a password made of a unique ID, which can be recorded and decrypted using an SDR.
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