RHEL 10 must enforce password complexity by requiring that at least one lowercase character be used.

STIG ID: RHEL-10-600240  |  SRG: SRG-OS-000070-GPOS-00038 |  Severity: medium (CAT II)  |  CCI: CCI-004066 |  Vulnerability Id: V-281183

Vulnerability Discussion

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 must be tested before the password is compromised.

Requiring a minimum number of lowercase characters makes password guessing attacks more difficult by ensuring a larger search space.

Check

Verify RHEL 10 enforces password complexity by requiring that at least one lowercase character be used with the following command:

$ sudo grep -s lcredit /etc/security/pwquality.conf /etc/security/pwquality.conf/*.conf
/etc/security/pwquality.conf:lcredit = -1

If the value of "lcredit" is a positive number or is commented out, this is a finding.

Fix

Configure RHEL 10 to enforce password complexity by requiring that at least one lowercase character be used by setting the "lcredit" option.

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

lcredit = -1