The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed or new passwords are established, the new password must contain at least one upper-case character.

STIG ID: RHEL-07-010120  |  SRG: SRG-OS-000069-GPOS-00037 | Severity: medium |  CCI: CCI-000192

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 need to be tested before the password is compromised.

Check

Note: The value to require a number of upper-case characters to be set is expressed as a negative number in "/etc/security/pwquality.conf".

Check the value for "ucredit" in "/etc/security/pwquality.conf" with the following command:

# grep ucredit /etc/security/pwquality.conf
ucredit = -1

If the value of "ucredit" is not set to a negative value, this is a finding.

Fix

Configure the operating system to enforce password complexity by requiring that at least one upper-case character be used by setting the "ucredit" option.

Add the following line to "/etc/security/pwquality.conf" (or modify the line to have the required value):

ucredit = -1