The correct answers are B, D, and E.
OBJ-3.2: First, you should change the username and default password since using default credentials is extremely insecure. Second, you should implement an allow list for any specific IP blocks with access to this application’s administrative web frontend since it should only be a few system administrators and power users. Next, you should implement two-factor authentication to access the application since two-factor authentication provides more security than a simple username and password combination. You should not rename the URL to a more obscure name since security by obscurity is not considered a good security practice. You also should not require an alphanumeric passphrase for the application’s default password. Since it is a default password, you can not change the password requirements without the vendor conducting a software update to the application. Finally, while it may be a good idea to conduct a penetration test against the organization’s IP space to identify other vulnerabilities, it will not positively affect remediating this identified vulnerability.