cyberstrikeus CIS Ubuntu Linux 18.04 LTS Benchmark v2.2.0 - Control 4.5.1.6
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Description
The pwquality difok option sets the number of characters in a password that must not be present in the old password.
Rationale
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.
Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.
Audit Procedure
Command Line
Run the following command to verify that the difok option in /etc/security/pwquality.conf is set to 2 or more:
grep -Pi '^\h*difok\h*=\h*([2-9]|[1-9][0-9]+)\b' /etc/security/pwquality.conf
Expected Result
difok = 2
Or higher.
Remediation
Command Line
Edit or add the following line in /etc/security/pwquality.conf to a value of 2 or more:
difok = 2
Default Value
difok = 1
References
- NIST SP 800-53 Rev. 5: IA-5
CIS Controls
v8 - 5.2 Use Unique Passwords - Use unique passwords for all enterprise assets.
v7 - 4.4 Use Unique Passwords.
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Assessment Status
Automated