The WIN_CERTIFICATE_UEFI_GUID AuthInfo defined in the UEFI spec mentioned that It is a signature across the image data and the Monotonic Count value. After clarification, we do the signature calculation, we put MonotonicCount after Payload. Cc: Liming Gao <liming.gao@intel.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Yonghong Zhu <yonghong.zhu@intel.com> Reviewed-by: Liming Gao <liming.gao@intel.com> Reviewed-by: Jiewen Yao <jiewen.yao@intel.com> Tested-by: Jiewen Yao <jiewen.yao@intel.com>