tagged: Nfc

• 2026-07-12

  Your Smart Diffuser Is an ESP32 With the Cloud Keys in Plaintext

  Pura's smart scent diffusers are cloud-locked ESP32 boards that talk to AWS IoT, gate the fragrance cartridges behind a signed NFC token, and ship with their per-device private key sitting unencrypted in flash. Here's the full teardown: pulling the firmware, MITMing the cloud, cracking the dual-bay NFC, and rebuilding both two-bay models on local ESPHome with no cloud at all.