Check template file extension name

Author: wchen-r7

modules/exploits/multi/fileformat/office_word_macro.rb

@@ -265,6 +265,11 @@ def get_template_path
 
   def exploit
     template_path = get_template_path
+
+    unless File.extname(template_path).match(/\.docx$/i)
+      fail_with(Failure::BadConfig, 'Template is not a docx file.')
+    end
+
     print_status("Using template: #{template_path}")
     @docx = unpack_docx(template_path)
 
@@ -277,7 +282,6 @@ def exploit
     print_status("Finalizing docm: #{datastore['FILENAME']}")
     docm = pack_docm
     file_create(docm)
-    super
   end
 
 end