Security researcher Dillon Beresford speaks to the press at the Black Hat conference in Las Vegas following his presentation which demonstrated how to hack into Siemens industrial control systems. Beresford specifically uncovered "replay attack" vulnerabilities in programmable logic controllers, or PLCs, which are used in organizations such as power plants to automate processes. He told the media that part of his motivation for the research was to debunk conventional thinking that SCADA attacks require deep pockets. This week, ICS-CERT issued an advisory warning of the bugs in the Berlin-based Siemens products.