Microsoft has acknowledged that the August updates have been disrupting Linux booting on dual-boot systems, according to an article from BleepingComputer.com.
Dual booting Windows and Linux is fairly common amongst those who don't want to deal with separate hardware, or on a tight budget, but users with dual-boot systems might encounter this issue if their Windows is fully up-to-date. The issue is with the new update patch of the Secure Boot Advanced Targeting or SBAT setting, that when present on a Windows device will block what it thinks are vulnerable boot managers.
The security update was released this month to patch GRUB, which is a popular open-source bootloader among many Linux distributions (i.e. Ubuntu, Zorin OS, Linux Mint, etc). If you do have the current patch and dual-boot between Windows and a Linux Distribution, an error will most likely display this error message that states "Verifying shim SBAT data failed: Security Policy Violation. Something has gone seriously wrong: SBAT self-check failed: Security Policy Violation".
The most likely solution to fix this issue is by disabling Secure Boot and then enabling it once you have fully installed your preferred Linux Distribution. There are possible alternatives to what I've suggested, and I am sure other places like Windows Central will put as well.
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