Details

The shorter the password, the lower the number of possible combinations that need to be tested before the password is compromised.

Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks. Password length is one factor of several that helps to determine strength and how long it takes to crack a password. Use of more characters in a password helps to exponentially increase the time and/or resources required to compromise the password.

Solution

Configure the Ubuntu operating system to enforce a minimum 15-character password length.

Add or update the following line in the ‘/etc/security/pwquality.conf’ file or a configuration file in the /etc/pwquality.conf.d/ directory to contain the ‘minlen’ parameter:

minlen=15

Supportive Information

The following resource is also helpful.

• https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_CAN_Ubuntu_16-04_LTS_V2R3_STIG.zip

This security hardening control applies to the following category of controls within NIST 800-53: Identification and Authentication.This control applies to the following type of system Unix.

References

• 800-53|IA-5(1)(a)
• CAT|II
• CCI|CCI-000205
• Rule-ID|SV-214962r610931_rule
• STIG-ID|UBTU-16-010240
• STIG-Legacy|SV-90157
• STIG-Legacy|V-75477
• Vuln-ID|V-214962

Source

• Tenable.com/audits