Fix removing the dropped files after exploitation

Author: zeroSteiner

modules/exploits/windows/local/cve_2017_8464_lnk_lpe.rb

@@ -134,9 +134,15 @@ def exploit
     register_files_for_cleanup(dll_path, lnk_path)
   end
 
+  def file_rm(file)
+    if file_dropper_delete(session, file) && @dropped_files && file_dropper_deleted?(session, file, true)
+      @dropped_files.delete(file)
+    end
+  end
+
   def generate_link(path)
     vprint_status("Generating LNK file to load: #{path}")
-    path << "\x00"
+    path += "\x00" # Do not use << here
     display_name = datastore['LnkDisplayName'].dup << "\x00" # LNK Display Name
     comment = datastore['LnkComment'].dup << "\x00"