Black Hat 2013 Security researchers have demonstrated how to exploit widely deployed SCADA systems to spoof data to the operator, and remotely control equipment such as pumps in oil pipelines.
The exploits were demonstrated live at Black Hat 2013 in Las Vegas on Thursday, and saw security engineers from energy sector process automation company Cimation remotely control the valves within a pretend oil well.
The simulation rig consisted of a liquid container that stood in for an oil well, connected to a pump that connected to an isolation valve, which then connected to a simulated tank; the system was controlled by a programmable logic controller (PLC) within a SCADA system.
Engineers Eric Forner and Brian Meixell demonstrated a way to remotely control the PLC that sends signals to devices on the simulated pipeline, and were able to turn pumps on and off – which in the real world could cause an oil pipeline to rupture. They also were able to send contrasting data to the Human Machine Interface (HMI) that sends data up to an operator.
"It's not rocket science, but it's extremely dangerous," Forner says. "In real life that would be a pipe blowout. That could be oil or acid or anything."
The researchers were able to do this because many PLCs are exposed to the internet with public IP addresses, and they frequently don't have Ethernet built-in, but instead have an old Ethernet module that plugs into their backplane. These Ethernet modules typically run an ancient version of Linux and are very easy to exploit, Forner says.
"It's usually just an embedded piece of hardware and runs VxWorks or some BusyBOX distro or RTOS, or some of them – God forbid – write their own OSs"
Once inside the Ethernet system, the engineers can then start to send commands to the PLC itself. Though companies implement safety logic in their PLCs that is designed to avoid damaging scenarios such as a pump being turned on in an already highly-pressurized system, this can be worked around, they said. Once the researchers gain access to the PLC, they can simply overwrite the logic with new safety logic that lacks these protections, and then enter malicious commands.
As of 2012, there are some 93,793 nodes on the public internet listening on port 502, according to the 2012 Internet Census, and the researchers suspect a large number of these are PLCs out in the field.
They were also able to spoof data to the Human Machine Interface (HMI) system which allows field workers and remote administrators to monitor the system. HMIs are frequently vulnerable to trivial attacks.
"A lot of them are Windows-based machines and woefully out of date, and the reason is you're in production and you never want them to go down. Every day you're not producing oil or some chemical is money down the drain," Forner says.
The team was able to start overloading the pretend oil tank, while outputting data to the HMI that said the fluid level in the tank was falling. This would cause an operator to typically pump more into the tank, so even if the underlying PLC has not been compromised, this provides another route of attack. In a final flourish, they uploaded their own binaries to the cracked HMI and had a game of Solitaire.
They also discussed ways to get at PLCs not kept on the company network. Hackers can do this by cracking their way into a company's enterprise network, then proceeding down the stack until they reach the PLC.
In an admission sure to induce brown trousers in people who live near oil pipelines, the researchers said that energy networks are very pooly protected.
"A lot of the firewalls that are implemented are put in place because people need to comply to a standard, and they end up leaving all traffic to pass," Meixell says.
"Even worse is no firewalls, where everything is on a flat network – anything from your SAP up to your WebSphere can talk directly. It'll be on the same LAN as your PLCs and controller hardware," Forner says with a hint of maniacal glee – an emotion that he radiated throughout the presentation, and which climaxed when the test rig began spraying dyed-green water onto the assembled cheering audience. ®