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

STIG ID: RHEL-07-010140  |  SRG: SRG-OS-000071-GPOS-00039 | Severity: medium |  CCI: CCI-000194

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 numeric characters to be set is expressed as a negative number in "/etc/security/pwquality.conf".

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

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

If the value of "dcredit" 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 numeric character be used by setting the "dcredit" option.

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

dcredit = -1