Secure Boot and Shim Signature

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Tasurinchi
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Secure Boot and Shim Signature

Post by Tasurinchi »

Hello everyone,

I hope you may help me,

I'm having the following issue. My former employer left my country and left me and my colleagues with the work computers. I wanted to turn mine into Linux, so I formatted the SSD and installed Mint. However, after a successful installation via Ventoy, I forgot my password :cry: .

Since the computer's Bios are admin locked, I have no chance to boot from another device to reinstall mint and format the SSD, so again, removed it, formatted it, installed Mint through ventoy aaaaand... Now I have a persistent "bad shim signature" error. I imagine the issue is due to secure boot which I cannot disable.

So the question is, why and how did I got it to work originally?
My ideas are that I by dumb luck, installed the correct MOK credentials without knowing what was I doing, and now it just won't repeat itself. Or maybe it has to do with formating the SSD in either MBR or GPT?
Last edited by LockBot on Sat Sep 23, 2023 10:00 pm, edited 1 time in total.
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mikeflan
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Re: Secure Boot and Shim Signature

Post by mikeflan »

If you have the space to store it, a full disk image of a well working system really is worth it. Especially in your case.
Something to consider if you every get back to normal.
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mikaelrask
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Re: Secure Boot and Shim Signature

Post by mikaelrask »

Hey have you tried hard reset the bios back to default settings? https://www.youtube.com/watch?v=bnWfB8LAmHc
CPU AMD Ryzen 9 7900
Graphic Card: AMD ATI Radeon RX 7900 XT/7900 XTX/7900M
Ram 32 GB ddr 5
Kernel: 6.5.0-14 generic
LM Cinnamon 21.3 edge
Tasurinchi
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Re: Secure Boot and Shim Signature

Post by Tasurinchi »

Hey!

Yes actually, there's no button, no cmos battery, nor you cannot short the chip. You have to solder wires to it and an interface, connect to an external programmer, and from then on, it only gets harder. The really dumb thing is that if I format the memory and reinstall windows 10, everything works like a charm, my former employer only cared about us destroying the proprietary information in the memory (even if it all was in the cloud as per internal policy), so Windows 10 recognizes the "pro" license from the Bios cache. But secure boot won't allow me any form of Linux.
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SMG
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Re: Secure Boot and Shim Signature

Post by SMG »

You may have run into an issue because Ubuntu updated the shims. See the explanation in this Ubuntu topic Verification failed: (0x1A) Security Violation from 22.04.1 live USB.

One person in another topic on this forum had issues installing LM21 versions, but was able to install LM20.3. Maybe you can see if you can install that and then run all the updates then do an upgrade in place to LM21 (and then LM21.1). Maybe that is a way to do an end-around until a newer release with the updated shims comes out.
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A woman typing on a laptop with LM20.3 Cinnamon.
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