Only works if the target is running Windows (paranoid people might be on Linux), so you'd probably want to slip in a malicious UEFI driver directly. Tools like

Only works if the target is running Windows (paranoid people might be on Linux), so you'd probably want to slip in a malicious UEFI driver directly. Tools like UEFITool can be used to analyze and modify the filesystem of a UEFI firmware image.