this post was submitted on 22 Aug 2024
149 points (96.3% liked)

Linux

48655 readers
1528 users here now

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.

Rules

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago
MODERATORS
 

Follow up to: “Something has gone seriously wrong,” dual-boot systems warn after Microsoft update

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 (Black Lotus did so using a vulnerability in the Windows bootloader, but a vulnerability in grub would be just as viable for this). Viewed purely from a security perspective, this was a legitimate thing to want to do.

...

The problem we've ended up in is that several Linux distributions had not shipped versions of grub with a newer security generation, and so those versions of grub are assumed to be insecure (it's worth noting that grub is signed by individual distributions, not Microsoft, so there's no externally introduced lag here). Microsoft's stated intention was that Windows Update would only apply the SBAT update to systems that were Windows-only, and any dual-boot setups would instead be left vulnerable to attack until the installed distro updated its grub and shipped an SBAT update itself. Unfortunately, as is now obvious, that didn't work as intended and at least some dual-boot setups applied the update and that distribution's Shim refused to boot that distribution's grub.

...

The outcome is that some people can't boot their systems. I think there's plenty of blame here. Microsoft should have done more testing to ensure that dual-boot setups could be identified accurately. But also distributions shipping signed bootloaders should make sure that they're updating those and updating the security generation to match, because otherwise they're shipping a vector that can be used to attack other operating systems and that's kind of a violation of the social contract around all of this.

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 63 points 4 months ago* (last edited 4 months ago) (5 children)

So they claimed it wasn't supposed to affect dual boots, yet it was specifically to patch a vulnerability in GRUB, something a Windows-only user has no reason of ever using (that I'm aware of)?

So how could this have affected anyone but people who dual boot? Sketchy.

[–] deafboy 2 points 4 months ago (3 children)

You, and 62 other people did not read the article.

[–] [email protected] -3 points 4 months ago (2 children)

I don't dual boot so I had no reason to read the article carefully.

[–] okamiueru 5 points 4 months ago (1 children)

But then again, you did comment on what the article was about. Which would make it relevant to know what the article was about.

[–] [email protected] -3 points 4 months ago* (last edited 4 months ago)

And I do, generally. But like I said, I did not read it carefully because I had no reason to.

So if they addressed what I said, I didn't read that part. 🤷🏻

load more comments (1 replies)