Vulnerability Discussion

Passwords must be protected at all times, and encryption is the standard method for protecting passwords. If passwords are not encrypted, they can be plainly read (i.e., clear text) and easily compromised.

Using more hashing rounds makes password cracking attacks more difficult.

Check

Verify the number of rounds for the password hashing algorithm is configured with the following command:

$ grep rounds /etc/pam.d/password-auth /etc/pam.d/system-auth

/etc/pam.d/password-auth:password sufficient pam_unix.so sha512 shadow rounds=100000 use_authtok
/etc/pam.d/system-auth:password sufficient pam_unix.so sha512 shadow rounds=100000 use_authtok

If a matching line is not returned in both files, or "rounds" is less than "100000", this a finding.

Add/modify the appropriate sections of the "/etc/pam.d/password-auth" file to match the following lines, ensuring that the "preauth" line is listed before pam_unix.so

Fix

Configure AlmaLinux OS 9 to use at least 100000 hashing rounds for hashing passwords.

Add or modify the following line in "/etc/pam.d/password-auth" and "/etc/pam.d/system-auth" and set "rounds" to "100000" or higher:

password sufficient pam_unix.so sha512 rounds=100000