Vulnerability Discussion
The system must use a strong hashing algorithm to store the password.
Passwords need to 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.
Satisfies: SRG-OS-000073-GPOS-00041, SRG-OS-000120-GPOS-00061
Check
Verify that the interactive user account passwords are using a strong password hash with the following command:
$ sudo cut -d: -f2 /etc/shadow
$6$kcOnRq/5$NUEYPuyL.wghQwWssXRcLRFiiru7f5JPV6GaJhNC2aK5F3PZpE/BCCtwrxRc/AInKMNX3CdMw11m9STiql12f/
Password hashes "!" or "*" indicate inactive accounts not available for logon and are not evaluated.
If any interactive user password hash does not begin with "$6", this is a finding.
Fix
Lock all interactive user accounts not using SHA-512 hashing until the passwords can be regenerated with SHA-512.