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Old 08-20-2012, 01:31 AM   #16
evo2
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Hi,

Quote:
Originally Posted by kedarp View Post
I did it from the recovery mode. Could change the permissions of the sudoers file as root.
But isn't it unsecure to get the access to root account from the recovery mode without a password?
But Thanks all for the help.
If someone has physical access to the machine, then all bets are off.

Evo2.
 
Old 08-20-2012, 08:32 AM   #17
byannoni
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Quote:
Originally Posted by kedarp View Post
I did it from the recovery mode. Could change the permissions of the sudoers file as root.
But isn't it unsecure to get the access to root account from the recovery mode without a password?
But Thanks all for the help.
If you want, you can make a root password with this:
Code:
sudo passwd root
 
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Old 08-20-2012, 12:58 PM   #18
towheedm
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Quote:
Originally Posted by kedarp View Post
I did it from the recovery mode. Could change the permissions of the sudoers file as root.
But isn't it unsecure to get the access to root account from the recovery mode without a password?
But Thanks all for the help.
There's an even worst downfall to this: It allows you to issue the startx command as root.

I'm now thinking Evo2 is the same person who responded to this post:
http://ubuntuforums.org/showthread.php?t=1842624

I still think it's insecure and I absolutely hate the idea of dropping to recovery ode without being ask for root's password.
 
Old 08-20-2012, 09:52 PM   #19
chrism01
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Like Evo2 said
Quote:
If someone has physical access to the machine, then all bets are off.
unless you've encrypted your files and stored the key elsewhere.

Remember that in the real world, there has to be a way to recover a borked system WITHOUT re-installing if at all possible.
You can add paswds to BIOS and GRUB, but if someone has physical access they can remove the disk and add it to another machine and mount it without running it; same as using 'linux rescue' mode if booted from the Install Media.
 
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Old 08-20-2012, 09:58 PM   #20
evo2
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Hi,
Quote:
Originally Posted by towheedm View Post
I'm now thinking Evo2 is the same person who responded to this post:
http://ubuntuforums.org/showthread.php?t=1842624
Was not me. I've never posted there.
Quote:
I still think it's insecure and I absolutely hate the idea of dropping to recovery ode without being ask for root's password.
So even if you can't get a root shell by booting this way, what is to stop a person with physical access booting from some removable media and then mounting the file system?

If you really are worried you should set a password for the bios (should be easy), and encrypt your filesystem (significant effort), and keep your machine in a physically secure location.

Evo2.
 
Old 08-21-2012, 04:03 AM   #21
kedarp
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Quote:
Originally Posted by byannoni View Post
If you want, you can make a root password with this:
Code:
sudo passwd root
The root account was there, and you can always su to root.
What I did in post #8, I tried to use the users sudo password with su.
So I got the "Authentication Failure" message. In Ubuntu,
the root password was never set and there was no password for root. So
it does not ask for root password in the recovery mode also.
Note the system asked for password in recovery mode when I set one.

What ubuntu users don't know, that the root account always exists without
a password. So it is better that they know about the root and set a password.

The thread is interesting.

Last edited by kedarp; 08-21-2012 at 04:13 AM.
 
Old 08-21-2012, 07:44 AM   #22
TobiSGD
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Quote:
Originally Posted by kedarp View Post
What ubuntu users don't know, that the root account always exists without
a password.
That is not quite true. In Ubuntu the root account is set to a password hash that doesn't match a password. So if you don't set up a password yourself you can't login as root or su to root. That is also the reason why the system doesn't ask for a password in recovery mode, you weren't be able to answer that question anyways. From https://help.ubuntu.com/community/RootSudo:
Quote:
By default, the Root account password is locked in Ubuntu. This means that you cannot login as Root directly or use the su command to become the Root user.
Quote:
The sulogin program in Ubuntu is patched to handle the default case of a locked root password.
 
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Old 08-21-2012, 11:27 PM   #23
TKH
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I would use another distro's live CD if I were you
 
  


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