Make a password policy part of your security plan
A comprehensive password policy is the first line of defense in a
well-rounded IT security plan. Many organizations even consider password
policies to have the same security priority as disaster recovery and Internet
defense, and rightfully so. This article will describe how to create a policy
and initiate strong password methods.
Password administration
Password administration is necessary to combat the forces that can compromise
your valuable electronic resources. The two main forces are social engineering
and brute force. Social engineering occurs when someone becomes familiar enough
with a person to guess likely passwords. Brute force methods attack systems
with systematically generated credentials attempting to guess a valid username
and password. Both of these two enemies are capable of eventually guessing a
valid password and then exploiting resources and data on a corporate network.
Protecting your resources from these attacks is achievable through developing a
solid password policy, diligence, and most importantly, using IT tools to
enforce the policy.
Enforcement
Historically, policies of all types are printed,
filed, and policed by internal efforts that gain sub par implementation and
effectiveness. To make a password policy effective, organizational support
needs to be gained from the top down to add credibility to your efforts.
Management needs to realize that the IT password policy is part of the
information security strategy and that enforcing it is essential. The most
effective enforcement method, however, is to use technology to ensure
compliance.
Your password policy needs to state exactly how it is to be implemented and
administered. It must outline what systems are affected by the policy, who is responsible for the different aspects of the policy,
and how to obtain support for questions or issues as they arise.
Obtaining password policy compliance requires that administrators be diligent
on several fronts. Here are some examples of things you can do to keep your
password policy effective:
- Run password scans and notify
users when a password is too easy and needs to be changed.
- Get all operating systems,
client-server applications, and other resources set to make users change
their passwords on a periodic basis.
- Examine workspaces for
passwords attached to keyboards or monitors.
- Train new employees properly
on the password policy—and train current employees when the policy is
implemented.
These tasks will add thoroughness and enhance compliance when enforcing a
password policy.
Matters of practice
To illustrate the need for careful password handling,
I like to refer to a situation everyone has dealt with. Think of your credit
card. Then, imagine that you have forgotten your PIN and you want to make a
cash advance on your account. Your bank will not disclose your PIN to you over
the telephone, nor will it verify the number if you have an idea of what it is.
This is because the bank realizes that a malicious user could perform some social
engineering to fraudulently use the card for cash advances.
Passwords for IT resources should be handled in a similar manner, and they
should be subject to several prohibitions. A password should never be:
- Written, e-mailed, or spoken.
- Shared with other people.
- Hinted at or made easy to
guess.
- Used in sync with or
duplicated by personal passwords or Web accounts.
- Shared when out of the
office.
- Typed in and saved in
electronic documents.
Password attributes
IT administrators can determine the complexity of the passwords that are
implemented in their systems. When implemented, the factors listed below can
all decrease the likelihood of password compromise. Different operating
systems, applications, or other resources may have different terms and implementations
for these attributes. Many of these password attributes will allow
administrators to increase the complexity of a password policy to boost
security, but beware of the inconveniences for users that arise as you make the
policy more complex.
- Expiration frequency—Set a time frame for how long a password is valid. The
more frequently passwords are changed the better, but you'll usually want
to have users change them at least every three months. Getting users
familiar with the password change process will streamline this task, so
user education is crucial.
- Character length—Set
a minimum length for a password. Six-character passwords seem to be the
minimum in a secure world, but the more, the better. A good practice is to
require that administrative passwords be 10 characters or more.
- Password composition—Mandate
that passwords require special combinations of letters, numbers,
non-alphanumeric characters, and case sensitivity. These attributes can
often be enforced by software. Your written policy can dictate that
passwords may not contain personal data (address or date of birth),
dictionary terms, organizational terms, and user-related words (name or
username).
- Invalid login attempts—Using
OS software, specify the number of times an account can attempt to
authenticate before being locked out and how long that account is locked
out before it can be released by an administrator.
- Password history—Specify
whether a password must be unique from passwords used in the past. For
example, users might be disallowed from reusing any of their previous 10
passwords.
- Timeout = Logout—Have
idle sessions disconnect from network resources after a specified period
of inactivity.
- Disable incremental
passwords—Disallow users from using incremental passwords such
as password, password2, password3, etc.
- Supporting efforts—Computer
BIOS passwords, file-level passwords, and other supplemental efforts can
also help solidify information security, especially on ultra sensitive
systems and documents.
NOS implementation
Enforcing your password policy by implementing its
parameters on your network operating system is an important step in making
passwords more effective. Many network operating systems will allow you to
enable password parameters. Let’s take a brief look at enabling strong
passwords in Windows 2000 and on the BSD OS family:
- Windows 2000—By default, Windows does not offer strong password
functionality as a requirement for all passwords. You can enable this
feature in Windows 2000 in the Group Policy. Once enabled, all new
passwords and password changes will be subject to the complexity
requirements. The complexity requirements are spelled out in this
MSDN article.
- BSD OS—In BSD-based
UNIX operating systems, you can implement security options for users quite
easily. For example, the /etc/login.conf file will allow you to
specify a minimum password length (minpasswordlen) and the option
to require a mixed-case password (mixpasswordcase) as
authentication properties.
Whatever NOS you are using, some research about your systems should allow
you to make use of their password features. Some systems may not have all
of the password capabilities you'd like, but being aware of their abilities
is a step in the right direction. Whatever parameters you are lacking will
need to be spelled out in your password policy in terms of how they will
be implemented and enforced.
Final word
When an IT department introduces a stronger password policy,
it needs to make sure that the users and the overall business goals remain
top priorities. A policy that is too confining can end up encouraging
users to write down their passwords in order to remember them, which can
defeat the effort altogether.
The amount of preparation and user education that IT puts forth will
determine the success of a password policy initiative. The effort is
worthless if users become unable to access the resources they need to do
their jobs. Proper planning, user training, and an IT staff motivated to
get the users familiar with the new password rules will enable users and
administrators to operate more securely.