Vulnerability Discussion

Increasing the time between a failed authentication attempt and reprompting to enter credentials helps to slow a single-threaded brute force attack.

Check

Verify RHEL 9 enforces a delay of at least four seconds between console logon prompts following a failed logon attempt with the following command:

$ grep -i fail_delay /etc/login.defs

FAIL_DELAY 4

If the value of "FAIL_DELAY" is not set to "4" or greater, or the line is commented out, this is a finding.

Fix

Configure the RHEL 9 to enforce a delay of at least four seconds between logon prompts following a failed console logon attempt.

Modify the "/etc/login.defs" file to set the "FAIL_DELAY" parameter to 4 or greater:

FAIL_DELAY 4