A security analyst needs to test it security of a server that resides in the company's DMZ. The analyst runs a scan on the server and discovers the following:

Port state service

21/tcp open ftp

25/tcp open smtp

| smnp-vuln-cve2010-4344:

| _ The SMNP server is not Exim: NOT VULNERABLE

| ssl-dh-params:

| VULNERABLE:

| Diffie-Hellman Key Exchange Insufficient Group Strength

|_State: VULNERABLE

143/tcp open imap

| ssl-dh-params:

| VULNERABLE:

| Diffie-Hellman Key Exchange Insufficient Group Strength

|_State: VULNERABLE

Which of the following should the analyst use next to test the security of the server?

1. Password cracker

2. Port scanner

3. Banner grabbing utility

4. vulnerability scanner

5. open relay SMTP testin