What's so secure about sudo?

[Shlomo Solomon]

This has bothered me for years and I decided to "get it off my chest".

For many years I used su to do administrative tasks, but "everyone"
uses sudo and the claim is that it's more secure than actually logging
in as root. 

In principal, of course, root login is not a good thing, but let's
remember something I've never seen discussed. I would assume that on
most systems the root password is MUCH more secure than that of a
regular user. Now if I give user david sudo privileges, anyone who
cracks david's (weak) password now has access to root privileges. 

And before anyone says that this is only a one-time authorization, what
if the guy who cracked david's password now does:
       sudo passwd root

So what's so secure about using sudo?   

-- 
Shlomo Solomon
http://the-solomons.net
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