But when ubuntu ask for updates we can press "Install Updates" and everything installs without filling in a password.
Not exactly true. It will ask for a password when something like a kernel gets updated. And try it with a non-admin user ;)
Is this a bug?
Nope.
Or just the way how ubuntu works?
Update Manager and USC do not use apt directly, they use a fork of PackageKit called aptdaemon. See: http://lists.debian.org/deity/2009/02/msg00000.html Aptdaemon already provides the following features:
- PolicyKit authorization allowing e.g. desktop user to update the cache (check for updates) passwordlessly
- Install packages from repositories or local file system, remove packages, update the cache and (safe) upgrade your system
Is think i the only annoying thing about using ubuntu
Security comes with a price. In this case a password ;)
Some additional information.
This is the method used to make it not ask for a password.