A cleartext transmission of sensitive information vulnerability in the NFC interface of multiple Milesight IoT device models running affected firmware versions allows an unauthenticated attacker with physical proximity to retrieve LoRaWAN ABP NwkSKey and AppSKey values and D2D keys via an NFC read operation. The exposed keys can be used to decrypt LoRaWAN traffic, forge uplink and downlink frames, submit falsified sensor data, issue supported device commands, and cause subsequent legitimate frames to be rejected.