Langner suspected the researchers had hit a wall, due to their lack of expertise with PLCs and industrial control systems. But curiously, Siemens had also gone silent. This was strange, Langner thought. It was, after all, Siemens controllers that were being attacked; the company had an obligation to analyze the malevolent code and tell customers what it might be doing to their systems. But after a couple of brief announcements the German company had made in July, it had gone mum.
