Title

The Ubuntu Operating system must be configured so that when passwords are changed or new passwords are established, pwquality must be used. (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. "pwquality" enforces complex password construction configuration and has the ability to limit brute-force attacks on the system.

Check Content

Verify the Ubuntu operating system has the libpam-pwquality package installed, by running the following command: # dpkg -l libpam-pwquality ii libpam-pwquality:amd64 1.4.0-2 amd64 PAM module to check password strength If "libpam-pwquality" is not installed, this is a finding. Verify the operating system uses "pwquality" to enforce the password complexity rules. Verify the pwquality module is being enforced by the Ubuntu Operating System, by running the following command: # grep -i enforcing /etc/security/pwquality.conf enforcing = 1 If the value of "enforcing" is not 1 or the line is commented out, this is a finding. Check for the use of "pwquality" with the following command: # sudo cat /etc/pam.d/common-password | grep requisite | grep pam_pwquality password requisite pam_pwquality.so retry=3 enforce_for_root If no output is returned or the line is commented out, this is a finding. If the value of "retry" is set to "0" or greater than "3", this is a finding. If "enforce_for_root" is missing from the configuration line, this is a finding.

Fix Text

Configure the operating system to use "pwquality" to enforce password complexity rules. Install the pam_pwquality package by using the following command: # apt-get install libpam-pwquality -y Add the following line to "/etc/security/pwquality.conf" (or modify the line to have the required value): enforcing = 1 Add the following line to "/etc/pam.d/common-password" (or modify the line to have the required value): password requisite pam_pwquality.so retry=3 enforce_for_root Note: The value of "retry" should be between "1" and "3".

Additional Identifiers

Rule ID: SV-219186r610963_rule

Vulnerability ID: V-219186

Group Title: SRG-OS-000480-GPOS-00225

Expert Comments

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