At this point we are ready to send data and fuzz through the channel. There are several public APIs available for sending packets through a VMBus channel. One of them is VmbChannelSendSynchronousRequest. It is one of the APIs used by VPCI and just requires a reference to the VMBCHANNEL to start working. The declaration is available in the vmbuskernelmodeclientlibapi.h header. We have highlighted where to use the VMBCHANNEL: