Title

The Red Hat Enterprise Linux operating system must be configured so that when passwords are changed the number of repeating characters of the same character class must not be more than four characters. (Cat II impact)

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 Content

The "maxclassrepeat" option sets the maximum number of allowed same consecutive characters in the same class in the new password. Check for the value of the "maxclassrepeat" option in "/etc/security/pwquality.conf" with the following command: $ sudo grep maxclassrepeat /etc/security/pwquality.conf maxclassrepeat = 4 If the value of "maxclassrepeat" is set to "0", more than "4" or is commented out, this is a finding.

Fix Text

Configure the operating system to require the change of the number of repeating characters of the same character class when passwords are changed by setting the "maxclassrepeat" option. Add the following line to "/etc/security/pwquality.conf" conf (or modify the line to have the required value): maxclassrepeat = 4

Additional Identifiers

Rule ID: SV-204414r809186_rule

Vulnerability ID: V-204414

Group Title: SRG-OS-000072-GPOS-00040

Expert Comments

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