Security check at uscis

Hi everyone,
Please I need advice, when my wife submit an enquiry regarding our case, the below was their reply, what does it mean? How long will it takes to get out of this? Please advice.your case has not cleared all required security checks at this time. Until we receive the results of these security checks, we cannot move forward on your case. We cannot predict when we will receive the results of these security checks. Please be assured that we will make every effort to make a decision in your case as soon as the security checks are complete