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.

The system must use a strong hashing algorithm to store the password.

Check

Verify that the pam_unix.so module is configured to use sha512 in /etc/pam.d/password-auth with the following command:

$ grep -E "password.*pam_unix.so.*sha512" /etc/pam.d/password-auth

password sufficient pam_unix.so sha512 shadow rounds=100000 use_authtok

If "sha512" is missing, or the line is commented out, this is a finding.

Fix

Configure AlmaLinux OS 9 to use the SHA-512 algorithm for password hashing.

Edit/modify the following line in the "/etc/pam.d/password-auth" file to include the sha512 option for pam_unix.so:

password sufficient pam_unix.so sha512 shadow rounds=100000 use_authtok