Middleware Security - Cybersecurity of power hardware is becoming increasingly critical with the emergence of smart and connected devices such as Grid-connected inverters, EVs and their chargers, microgrid controllers, energy storage / energy management controllers, and smart appliances. Cyber-attacks on power hardware have had far-reaching and widespread impacts. For such cyber-physical systems, security must be ensured at all levels in the design - hardware, firmware, software and interfaces. Although previous approaches to cybersecurity have focused mainly on vulnerabilities in the firmware middleware, or software, vulnerabilities in the hardware itself are hard to identify and harder to mitigate, especially when most hardware components are proprietary and not examinable. This paper presents one approach to mitigate this conundrum - a completely open-source implementation of a microcontroller core along with the associated peripherals based on the well-known RISC-V instruction set architecture (ISA). The proof-of-concept architecture presented here uses the “Shakti” E-Class microcontroller core integrated with a fully custom PWM controller implemented in Verilog, and validated on a Xilinx Artix FPGA. For critical applications such designs may be replicated as a custom ASIC thereby guaranteeing total security of the computing hardware.