IoT projects and security with RISC-V

Hi all,

I wanted to reach out because I have been working on end-to-end IoT solutions and till now I have been using MCUs based on ARM-Cortex M series. So my question is if I want to use the HiFive Rev-B board to connect the sensors using different communication protocols and since RISC-V is an open source architecture. Will there be a security of firmware being uploaded in the HiFive development board like no one can easily do reverse engineering because of its open source ISA nature?

Thanks,
Akshay