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. Use of "pwquality" enforces complex password construction configuration and has the ability to limit brute-force attacks on the system.
OL 8 uses "pwquality" as a mechanism to enforce password complexity. This is set in both of the following:
/etc/pam.d/password-auth
/etc/pam.d/system-auth
Note: The value of "retry" set in these configuration files should be between "1" and "3". Manual changes to the listed files may be overwritten by the "authselect" program.
Satisfies: SRG-OS-000069-GPOS-00037, SRG-OS-000070-GPOS-00038
Check
Verify the operating system uses "pwquality" to enforce the password complexity rules.
Check for the use of "pwquality" with the following commands:
$ sudo cat /etc/pam.d/password-auth | grep pam_pwquality
password required pam_pwquality.so retry=3
$ sudo cat /etc/pam.d/system-auth | grep pam_pwquality
password required pam_pwquality.so retry=3
If both commands do not return a line containing the value "pam_pwquality.so" or the line is commented out, this is a finding.
Fix
Configure OL 8 to use "pwquality" to enforce password complexity rules.
Add the following line to both "/etc/pam.d/password-auth" and "/etc/pam.d/system-auth" (or modify the line to have the required value):
password required pam_pwquality.so retry=3