Linux Security Cookbook [Electronic resources] نسخه متنی

Recipe 9.3 Finding Accounts with No Password

9.3.1 Problem

You want to detect local login
accounts that can be accessed without a password.

9.3.2 Solution

# awk -F: '$2 == " { print $1, "has no password!" }' /etc/shadow

9.3.3 Discussion

The worst kind of password is no password at all, so you want to make
sure every account has one. Any good password-cracking program can be
employed herethey often try to find completely unprotected
accounts firstbut you can also look for missing passwords
directly.

Encrypted passwords are stored in the second field of each entry in
the shadow password database, just after the username. Fields are
separated by colons.

Note that the shadow password file is readable only by
superusers.

9.3.4 See Also

shadow(5).