IoT devices are ubiquitous today. Many of these devices use RF based communication techniques to connect to other devices or to receive commands from remote controls in near field. Many devices like smart tube lights have dual mode operation, in which they connect over the internet for interfacing with a mobile app or via RF with a local remote. RF based communication interface introduces an all new attack surface on IoT devices.
Software Defined Radios (SDR) are a versatile piece of hardware that can change reception and transmission profiles based on software configuration. SDRs are available in half-duplex (only reception or transmission at a time) or full-duplex mode (reception and transmission simultaneously). Affordable SDRs like HackRF have given rise to the recent SDR revolution among radio enthusiasts. These SDRs can be used to analyze the signal transmitted between IoT devices and transmit rogue messages. In this article we discuss some of the common attacks that work by exploiting the signal transmission and how some new devices are mitigating those attacks.
The most common type of attacks are based on capturing a command sequence and retransmitting it later. This is fairly easy to do using an SDR. The first step is to find out …