Garrett: What is an SBAT and why does everyone suddenly care Matthew Garrett <a href="https://mjg59.dreamwidth.org/70348.html" rel="nofollow">describes the role of the Secure Boot Advanced Targeting mechanism</a> and how it played into the recent Windows upgrade problems. So why is this suddenly relevant? SBAT was developed collaboratively between the Linux community and Microsoft, and Microsoft chose to push a Windows update that told systems not to trust versions of grub with a security generation below a certain level. This was because those versions of grub had genuine security vulnerabilities that would allow an attacker to compromise the Windows secure boot chain, and we've seen real world examples of malware wanting to do that. https://lwn.net/Articles/986844/