added an unless to wrap around the print and report_creds func for nas module to only execute if ftpuser and ftppass is non-blank

modules/auxiliary/scanner/misc/dahua_dvr_auth_bypass.rb

@@ -167,17 +167,19 @@ class Metasploit3 < Msf::Auxiliary
     if /[\x00]{16,}(?<ftpuser>[[:print:]]+)[\x00]{16,}(?<ftppass>[[:print:]]+)/ =~ data
       ftpuser.strip!
       ftppass.strip!
-      print_good("#{peer} --  NAS Server: #{server}")
-      print_good("#{peer} --  NAS Port: #{port}")
-      print_good("#{peer} -- FTP User: #{ftpuser}") unless ftpuser.blank?
-      print_good("#{peer} -- FTP Pass: #{ftppass}") unless ftppass.blank?
-      report_creds(
-        host: server,
-        port: port,
-        user: ftpuser,
-        pass: ftppass,
-        type: "FTP",
-        active: true)
+      unless ftpuser.blank? || ftppass.blank?
+        print_good("#{peer} --  NAS Server: #{server}")
+        print_good("#{peer} --  NAS Port: #{port}")
+        print_good("#{peer} -- FTP User: #{ftpuser}")
+        print_good("#{peer} -- FTP Pass: #{ftppass}")
+        report_creds(
+          host: server,
+          port: port,
+          user: ftpuser,
+          pass: ftppass,
+          type: "FTP",
+          active: true)
+      end
     end
   end