sudo without password

[ubuntu at rio.vg]

Derek Broughton wrote:
> 
> Even if it was "block mail" (or separate options for sending and receiving)
> it would be too difficult for the average user.

That's why Linux distro's that install iptables rules by default only
block the incoming ports, so things like getting mail aren't an issue.
It won't stop malware from making connections out, but it's a good
buffer that doesn't cause any problems for desktops that shouldn't be
listening anyway.  It's also nice for those times when someone knows
just enough to be dangerous.  For instance, if you install the Ubuntu
nfs packages in order to mount your files from a server, portmap starts
listening to the net.  If you know what you're doing, you can change
this behavior, but just having the firewall there blocking most incoming
connections is a good practice.

> I agree.  This is what ZoneAlarm does in Windows, and I think it's the
> correct model (regardless of whether ZA is actually a good firewall).  The
> problem comes with how (& who) the firewall program asks when servers try
> to access the net.

Not only that, but I'm not sure there's a method for iptables to hold
the connection while it asks another program if it's alright to allow.
And, of course, it'd never work for servers... but hopefully the server
is being run by someone who knows what they are doing...

>>> One thing I haven't seen for Linux is something like ZoneAlarm,
> 
> Oh look - some mysterious "ubuntu" said that :-)

A long while back I had some problems unsubscribing to a couple of
mailing lists, so now I just create a new alias for each mailing list.
Makes the whole thing easier for procmail, too. :)

>>> that would bring up a dialog when something tries to make outgoing
>>> connections for filtering aswell.  At this point, it isn't nearly
>>> as big of an issue, since Linux has far fewer malware issues as
>>> Windows.
> 
> I suppose it depends how you look at it.  My office-mate, a very capable
> geek, just got root-kitted.  He was running without a firewall (at a
> university)!  Everybody who runs servers needs to run a firewall.  Aunt
> Tillie may not need one if she's got no server ports open and likely a NAT
> router between her and the Internet, anyway, but once you start opening
> ports just to connect the two computers on your desk, you're in trouble.

Right now, Aunt Tillie might not need one, but as Linux makes more
inroads on the desktop, there will be more e-mail trojans targeted at
Linux users.  Obviously, it shouldn't get as bad as it was for awhile in
Outlook, where e-mail could call activex at will, but more of the "Click
to see the dancing baby" type of trojans.  These can and will infect
linux boxes.

The attacker may not even be interested in root.  Commonly, they're
trying to create an army of zombie machines to DDoS someone.  You don't
need root for that.

Linux distros are going to need to change their way of thinking in the
future.  Currently, it's very server-centric, preventing outside
attackers from getting in.  For desktops, it's the user that just opened
the door for the pretty horse that's the issue.

(Something just occurred to me, perhaps someone could put my mind to
rest: Sudo only asks for a password once every x number of minutes.
Could someone write a trojan that sits there waiting for the user to run
sudo, then runs it itself right afterward, bypassing the password prompt?)