The AsrDrv101.sys and AsrDrv102.sys low-level drivers in ASRock RGBLED before v1.0.35.1, A-Tuning before v3.0.210, F-Stream before v3.0.210, and RestartToUEFI before v1.0.6.2 expose functionality to read/write data from/to IO ports. This could be leveraged in a number of ways to ultimately run code with elevated privileges.