An IR blaster is a device that sends infrared signals to control nearby electronics, such as TVs, media players, or other consumer devices that still accept remote-control commands. It works over a short range and usually requires line of sight, so it is not a networked control channel in the usual sense.
In cyber security, IR blasters matter because they can bridge digital systems and older hardware. A small embedded device, phone accessory, or custom board can automate actions on equipment that lacks authentication or modern logging. That can be useful for legitimate testing, but it can also let an attacker trigger physical-world actions without touching the target. Defenders should treat infrared-controlled equipment as part of the attack surface and account for hidden controllers, unattended rooms, and devices that respond to simple command codes.