remote root

Posted Feb 15, 2007 21:21 UTC (Thu) by rfunk (subscriber, #4054)
In reply to: Linux botnets by tetromino
Parent article: Linux botnets

This is an old debate. But you'll be hard-pressed to find an experienced professional
sysadmin who will allow remote root logins.

Allowing direct root access means that root access is not revokable per-admin; if the
password is somehow compromised (e.g. an admin is fired or is careless with the
password) you have to change the root password and communicate that to all admins
(with the associated insecurity of that communication). If admins are getting root from
their own accounts, then it's sufficient to disable or re-password a single admin's account
without affecting other admins.

So in the sudo case, if that one password is guessed, it's easier to recover than in the
single remote-root case.

Just running a root shell is dangerous. It's much better to be root only for what needs to
be done as root, to avoid accidents or possibly tripping over sabotage (e.g. someone
having gotten in and messing with your ls command).

This slashdot comment is one place that covers the issue well:
http://it.slashdot.org/comments.pl?sid=180864&cid=149...

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remote root

Posted Feb 16, 2007 0:25 UTC (Fri) by dd9jn (✭ supporter ✭, #4459) [Link] (1 responses)

"Allowing direct root access means that root access is not revokable
per-admin; if the password is somehow compromised"

FWIW, I was talking about public key authentication for root access. This also means that revoking access is as simple as deleting one line from authorized_keys.

Where do you see the problem? I agree that logging of access is not as it should be but it is still available and come one, having root access does on most systems mean you have all the power to manipulate the logs. So why care.

remote root

Posted Feb 19, 2007 15:54 UTC (Mon) by hein.zelle (guest, #33324) [Link]

> Where do you see the problem? I agree that logging of access is not as it
> should be but it is still available and come one, having root access does
> on most systems mean you have all the power to manipulate the logs. So
> why care.

One reason I care is that it's easy to accidently turn password authentication back on. On many debian systems I've seen, the option UsePAM (on by default) effectively allows password authentication, even when PasswordAuthentication is off. This is not the case on the latest ubuntu, but dangerous nevertheless. I'd rather have an ssh login as a regular user, and then become root using su.

What is the reasoning behind not using su to become root? I understand the password will go over the line, but it's encrypted. Is this advised against for fear of keyloggers or so?