Microsoft’s latest monthly security update has wreaked havoc on dual-boot Windows and Linux operating systems. The software giant released a security patch last week to fix a two-year-old vulnerability in the open-source GRUB boot loader used by many Linux machines. Microsoft’s patch wasn’t supposed to affect dual-boot machines, but many have discovered it and it’s now preventing their Linux installations from booting properly.
Ars Technica Reports Many dual-boot Linux users are seeing “Security policy violation” messages, along with “A serious error has occurred” errors. There are reports of issues all over the Reddit, Ubuntu Forumsand elsewhereDistributions like Ubuntu, Debian, Linux Mint, Zorin OS, and Puppy Linux are affected by the patch released by Microsoft.
The update was supposed to fix a vulnerability that allowed hackers to bypass Secure Boot, a technology widely used in Windows and Linux distributions to ensure that malicious firmware is not loaded onto devices during boot. He said earlier this month Microsoft said it will apply a “Secure Boot Advanced Targeting (SBAT) update to prevent vulnerable Linux boot loaders that could have an impact on Windows security,” but the update will not apply to dual-boot systems running Windows and Linux, so it “should not impact these systems.”
Microsoft has not commented on the issues caused by its update, but there are Alternative solution For Ubuntu users, this involves disabling Secure Boot at the BIOS level and then logging into your Ubuntu user account and opening a terminal to delete Microsoft’s SBAT policy.
Microsoft has been using Secure Boot in Windows for years, and has made it a prerequisite for Windows 11 to use the technology to secure your device against BIOS-attacking rootkits. Researchers have discovered several vulnerabilities in Secure Boot over the years, and recently it was discovered that Secure Boot is completely disabled on many computers.