Title

RHEL 8 passwords must have a minimum of 15 characters. (Cat II impact)

Discussion

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 increase exponentially the time and/or resources required to compromise the password. RHEL 8 utilizes "pwquality" as a mechanism to enforce password complexity. Configurations are set in the "etc/security/pwquality.conf" file. The "minlen", sometimes noted as minimum length, acts as a "score" of complexity based on the credit components of the "pwquality" module. By setting the credit components to a negative value, not only will those components be required, they will not count towards the total "score" of "minlen". This will enable "minlen" to require a 15-character minimum. The DoD minimum password requirement is 15 characters.

Check Content

Verify the operating system enforces a minimum 15-character password length. The "minlen" option sets the minimum number of characters in a new password. Check for the value of the "minlen" option with the following command: $ sudo grep -r minlen /etc/security/pwquality.conf* /etc/security/pwquality.conf:minlen = 15 If the command does not return a "minlen" value of 15 or greater, this is a finding. If conflicting results are returned, this is a finding.

Fix Text

Configure operating system to enforce a minimum 15-character password length. Add the following line to "/etc/security/pwquality.conf" (or modify the line to have the required value): minlen = 15 Remove any configurations that conflict with the above value.

Additional Identifiers

Rule ID: SV-230369r858785_rule

Vulnerability ID: V-230369

Group Title: SRG-OS-000078-GPOS-00046

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