The Red Hat Enterprise Linux operating system must be configured so that passwords are a minimum of 15 characters in length.

STIG ID: RHEL-07-010280  |  SRG: SRG-OS-000078-GPOS-00046 |  Severity: medium |  CCI: CCI-000205 |  Vulnerability Id: V-204423 | 

Vulnerability 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 exponentially increase the time and/or resources required to compromise the password.

Check

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 in "/etc/security/pwquality.conf" with the following command:

# grep minlen /etc/security/pwquality.conf
minlen = 15

If the command does not return a "minlen" value of 15 or greater, this is a finding.

Fix

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