634
“Something has gone seriously wrong,” dual-boot systems warn after Microsoft update
(arstechnica.com)
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
Community icon by Alpár-Etele Méder, licensed under CC BY 3.0
I was interested too. It seems Microsoft has released a patch that blacklists vulnerable grub versions from being able to be secure booted even if they are signed properly:
https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2022-2601
The link was at the top of the article.
Maybe this update somehow affects your UEFI firmware, and it installs a list in there?