The Corsair Composite Virtual Input Device is a driver associated with Corsair's peripheral devices, such as keyboards, mice, and other input devices, that use specialized features, like custom macros, RGB lighting control, or integration with Corsair's iCUE software. The "composite" aspect indicates that the device can serve multiple functions (e.g., input device + lighting controller) through a single USB connection, and the virtual input device refers to the functionality that allows communication with the system as a multi-functional device.

When you plug in a Corsair peripheral that requires special software support (like a Corsair RGB keyboard or mouse), Windows may automatically attempt to install the relevant drivers, including the Corsair Composite Virtual Input Device driver. If the driver isn't installed automatically, it can prevent certain advanced features from working, such as customizable key mappings, macro assignments, and lighting effects.