I have no idea if there’s a granular object permission that could give access to the MBR of a disk. I’ve thankfully never had to dig that deep into Windows internals.

I’ve had to work with SDDL before to setup granular permissions for WMI monitoring on a whole lot of computers and my god, did it make me love the Cloud and Linux. I can’t emphasize enough how unintuitive setting these permissions is creates systemic over privileging.