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(bouncy intro music)

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- [Instructor] So, I've interrupted GRUB.

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I'm in the menu here. Let's do an e for edit.

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Let's look for kernel line.

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Here we go, here's the first kernel line.

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Let's say CMD ARG, TRY ONE init = bin/bash.

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And then let's look for another one.

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Got another one here.

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Let's go CMD ARG TRY TWO

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init = bin/bash

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and let's try to boot that.

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Alright, looks like it booted and I got a shell prompt here.

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I don't have to log in.

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How many things have we got in /bin?

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1400. It's got a lot.

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Got any block devices?

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Yeah, it sees three discs, processes,

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yeah, there's a lot of kernel threads,

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all these kworkers.

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And all these /3 things are also kernel stuff.

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In fact, this is pretty much all kernel stuff

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except for the ps and the grip.

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If we do pstree, do we have that command?

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There's like no processes, right?

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All we have is the shell, but we have our discs.

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And this could be handy, for example,

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if you forgot your root password.

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This also could be handy if you were trying to be malicious.

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So be careful if someone can get to your console,

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they potentially can interrupt GRUB

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and get into a shell as root, right.