try to run a Magic Lantern (a third party 'firmware' for some Canon cameras) version for a Canon EOS 5D III on a Canon EOS 5D II or Canon EOS M6.
There is no similarity between manufacturers, let alone between most camera models from the same manufacturer. While it is possible, it seems highly unlikely that a system with limited connectivity and little user-population such as a DSLR gets targeted by malware.
