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Re: shared root account

This is completely off-topic at this point, but there are a few uses
of sudo.  The original poster trusts his admins, and wants to give
them all root privs without the hassle of having them all use one
account.  Sudo is not enforcing anything in this case, it is merely
a) allowing convenience by allowing the user to effectively choose
their own root passwd.
b) allowing a form of audit trail; true, it's easy enough to bypass,
but someone trusted wouldn't go out of their way to bypass it.  It's
good for when (for example) samba suddenly stops working, instead of
checking /root/.bash_history for "<editor> /etc/smb.conf", running
`last` to see when root has logged in since it broke, etc etc,
you simply check your logs for the last time someone sudo'd "<editor>
smb.conf".  Make it policy for admins to not use `sudo bash`, or
anything similar.

What you people are talking about is adding privs to an untrusted
account.  The (ridiculous) example given, of allowing a user to
run /bin/cat, is similar doing a `chown root:<untrusted user> /bin/cat;
chmod 4770 /bin/cat`.  It's dangerous.  What a _sane_ admin would do,
if the user needed to view a file, is provide the argument to cat that
was required.   "<username> ALL=(root) /bin/cat /etc/[a-zA-Z]".  Or
specify the exact filename.  If it's an untrusted user, they should
be given as little leeway as possible.  Allowing them to cat any file
on the system is just stupid.

On Sat, Jul 07, 2001 at 02:10:09AM +0100, Eric E Moore wrote:
> Resent-Date: Fri, 06 Jul 2001 21:11:34 -0400
> >>>>> "Ethan" == Ethan Benson <erbenson@alaska.net> writes:
> Ethan> or even seemingly innocuous things like less or even cat.
> Less is a problem, yes, as is anything else with a shell escape.
> Ethan> sudo less anything !/bin/sh whoami r00t!
> Ethan> echo me ALL=ALL > s sudo 'cat s >> /etc/sudoers'
> doesn't work.  the >> is a shell redirection, but sudo doesn't
> evaluate in a shell.  
> $  echo me ALL=ALL > s
> $ cat s
> me ALL=ALL
> $ sudo 'cat s > foo'
> sudo: cat s > foo: command not found
> $ sudo cat s \> foo
> me ALL=ALL
> cat: >: No such file or directory
> cat: foo: No such file or directory
> I would be very shocked if you could compromise a system with a
> sudoers entry of:
> me hostname = (root) /bin/cat
> Ethan> sudo is a very large cannon which is difficult to keep aimed
> Ethan> away from the foot...
> That it is.  But then, the root password is basically a very large
> cannon built into your shoe.
>   -Eric
> --  
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"... being a Linux user is sort of like living in a house inhabited
by a large family of carpenters and architects. Every morning when
you wake up, the house is a little different. Maybe there is a new
turret, or some walls have moved. Or perhaps someone has temporarily
removed the floor under your bed." - Unix for Dummies, 2nd Edition
        -- found in the .sig of Rob Riggs, rriggs@tesser.com

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