Oh, you're absolutely right that modifying SSD firmware gives you a lot of fun possibilities for hijacking a machine, but that is not new either, it's a threat

Oh, you're absolutely right that modifying SSD firmware gives you a lot of fun possibilities for hijacking a machine, but that is not new either, it's a threat vector that has been known and investigated for many years now. Here's someone running Linux on an HDD controller in 2013: https://spritesmods.com/?art=hddhack&page=1 https://spritesmods.com/?art=hddhack&page=1 It's well known that SSD vendor security is usually atrocious; these companies do not have much experience building secure-boot systems, and there are often vendor-specific backdoor commands and such. You absolutely do not need the resources of a state actor to pull that off; a good reason and 5-6 digits' worth of (competent) security researcher time ought to do it. I've spent half of my life breaking systems that try a lot harder to have secure boot than SSDs, as a hobby. Indeed, IOMMU support is critical in the modern hardware ecosystem. Honestly, any system that does not use them by default for all off-chip peripherals in 2021 is just unsuitable for any kind of sensitive use case. That, plus FDE with hashtree authentication, eliminates SSD compromise as an attack vector.