看看这个，关于密码的...(zz)

[pihou]

===========================================================
Ubuntu Security Notice USN-262-1 March 12, 2006
Ubuntu 5.10 installer vulnerability
CVE-2006-1183
===========================================================

A security issue affects the following Ubuntu releases:

Ubuntu 5.10 (Breezy Badger)

The following packages are affected:

base-config
passwd

The problem can be corrected by upgrading the affected package to
version 2.67ubuntu20 (base-config) and 1:4.0.3-37ubuntu8 (passwd). In
general, a standard system upgrade is sufficient to effect the
necessary changes.

Details follow:

Karl Øie discovered that the Ubuntu 5.10 installer failed to clean
passwords in the installer log files. Since these files were
world-readable, any local user could see the password of the first
user account, which has full sudo privileges by default.

The updated packages remove the passwords and additionally make the
log files readable only by root.

This does not affect the Ubuntu 4.10, 5.04, or the upcoming 6.04
installer. However, if you upgraded from Ubuntu 5.10 to the current
development version of Ubuntu 6.04 ('Dapper Drake'), please ensure
that you upgrade the passwd package to version 1:4.0.13-7ubuntu2 to
fix the installer log files.

[firehare]

sudo apt-get update
sudo apt-get dist-upgrade

就可以了！