Most organisations utilise passwords as a method of authenticating users as part of their access control solution for their systems. 7 Elements have often found poor password policy or insufficient policy enforcement can be a severe point of failure in an otherwise secure system. For password authentication to be effective the security provided by using passwords must remain robust regardless of persistent attacks originating from either human or computer sources. Organisations can take steps to ensure that the passwords used to access their systems are sufficiently strong by employing a robust password policy. This guidance lays out some key steps organisations can take to develop a robust password policy and therefore help ensure that strong passwords are used on their systems.
Password Formation Guidance
To ensure that users have strong passwords the following basic guidelines on how passwords are formed may be used as part of a robust password policy. A robust password policy should stipulate that a password has the following properties.
• Passwords should be a minimum of nine characters long. They should also be sufficiently complex to offset the likelihood of a successful brute force attack or guessing of the password.
• Passwords should not contain personal information such as names, addresses, birthdays, car registrations, ID numbers etc.
• Complex passwords should consist of at least four of the following elements however, users should be free to choose from any of these categories:
- Uppercase letters
- Lowercase letters
- Punctuation marks
- Mathematical or other conventional symbols
• Use of common passwords should be banned. Common passwords can be compiled from the many repositories of passwords released after major account hacks.
• A history of old password hashes should be kept. This should be used to prevent users from re-using their previous passwords.
• Accounts should be locked out after a number of failed access attempts. This is ordinarily set to three attempts. This helps to reduce the likelihood of a successful brute force attack against accounts.
• Passwords should be changed at regular intervals. However, organisations should be aware that constantly enforcing password changes may cause users to develop password generation fatigue. This may result in users employing insecure coping strategies, such as writing passwords down or using non-complex passwords. This could eventually degrade the security of password authentication.
• Password reuse should be limited so that unique passwords are not used across a single user’s multiple accounts. Furthermore passwords across accounts should not be similar permutations of the original password.
Password Security Augmentation Elements
In developing a password policy it is crucial that the system is practical for users. This can be achieved by ensuring that verification methods impose a minimal burden on users. To assist in this the following factors should be considered in developing a password policy.
• Memorability: Passwords must not be so complex as to be difficult to recall.
• Guessability: Passwords should be hard to guess. This means family, colleagues, friends and social engineers should not be able to guess passwords by exploiting the varying degrees of intimacy with a password holder. Passwords should not contain meaningful dates, pet names, addresses, hobbies, interests or otherwise.
• Observability: Passwords should be entered easily. If a password is overly time consuming to enter this enhances the ability of shoulder surfers to accurately observe password entry.
• Recordability: Password entry must be secure. Users should become naturally wary of highly observable key press combinations for instance, the password “qwerty” is highly recordable due to the sequential means of entry on standard keyboards. As characters are being typed into the password field they should also be immediately obfuscated to avoid screen recorders from recording password input. The workstations in use must also be secure to ensure keyloggers are not in operation.
• Complexity: A minimum password length combined with relative complexity is essential. Passwords do not need to be overly complicated to remember but instead fortified through the discussed elements of augmentation to prevent the success of current and emerging password hacking and encrypted hash cracking techniques.
For a more robust approach to password management, take a look at our guidance on using a passphrase.