

You’re in the front of a Linux computer, you need a root access. What do you do? - jolenzy
http://www.jovicailic.org/2013/04/how-to-get-to-linux-root/

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pif
If you find the LILO prompt instead of the GRUB screen, use the option
"init=/bin/sh" instead.

As already pointed, this is not an attacking method, but just a recovery
method. From the POV of security, getting physical access to the console is
already bad.

~~~
jolenzy
Of course, totally agree. Yes, thanks for the LILO tip.

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jaryd
This was how the RHCE (Red Hat Certified Engineer) exam begun when I took it a
few years back...

However, instead of selecting "recovery mode" you had to edit the boot line
and add a "s" for single user mode.

~~~
jolenzy
I had this question on a job interview for a system admin role. It was the
first technical question :)

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drinchev
If you have physical access to a Linux computer, then your options are
unlimited. Manipulating grub could be one of it.

Things that come in my mind :

\- Use USB Flash/CD to boot something else, mount the hard-drive and do some
nasty stuff to passwd file.

\- If you have your BIOS locked, you can simply remove the hard drive and use
another box to do the same.

\- If you got your BIOS locked with a password, you can simply remove the
battery for 1-2 minutes and put it back!

\- No access to the battery?! Remove the hard drive, boot from CD/usb key (
since there is no hard drive almost every BIOS will search for something to
boot from ) and flash the BIOS :D

No system is secured if you have physical access to the hardware.

~~~
jolenzy
Great ideas! Of course, system can't be secure when you have physical access
to the hardware.

What I shared is is not an attacking method, but just a recovery method, which
was helpful for me recently, so I hoped that it can be helpful to someone else
as well.

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dpedu
Assuming there's no grub password set. And assuming you don't need a password
to reboot it.

~~~
jolenzy
Exactly. It's not any attacking method, but can be handy sometimes.

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DanBC
If you're in front of an HP-UX machine you want 'single user mode'.

([http://www.cyberciti.biz/faq/hpux-booting-into-single-
user-m...](http://www.cyberciti.biz/faq/hpux-booting-into-single-user-mode/))

~~~
jolenzy
I didn't know about this. Thanks for the tip, goes to my notes.

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qwerta
My disk is encrypted. Bootloader, kernel and encryption keys are with me on
USB flash. Good luck trying this approach.

~~~
peterwwillis
A DMA, cold boot or network attack might work :)

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joshguthrie
Nice, this is how we usually get (unauthorized) root access on our school's
*NIX systems.

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BrokenPipe
This is not HN material

~~~
DanBC
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