Ubuntu OS must enforce a delay of at least four seconds between logon prompts following a failed logon attempt.

Limiting the number of logon attempts over a certain time interval reduces the chances that an unauthorized user may gain access to an account.

Verify Ubuntu OS 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.

Configure the Ubuntu OS 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