Industrial control system (ICS) operators and owners have found themselves in an unenviable position. Once air-gapped, serial-based critical industrial control systems are now becoming more and more connected. And while many of the systems themselves have not changed, the networking world around them has changed dramatically, introducing vulnerabilities and threats that had been nearly non-existent ten or 20 years ago. Each networked connection from the control network to the corporate network is another potential avenue of attack. Control networks are designed to be static and predictable, but more and more commercial off-the-shelf applications and operating systems, as well as routable protocols, are now being introduced. This is creating more complexity with no greater visibility leaving operators blind to what is on their networks.
The HAVEX worm is making the rounds again. As Cisco first reported back in September 2013, HAVEX specifically targets supervisory control and data acquisition (SCADA), industrial control system (ICS), and other operational technology (OT) environments. In the case of HAVEX, the energy industry, and specifically power plants based in Europe, seems to be the primary target. See Cisco’s security blog post for technical details on this latest variant.
When I discuss security with those managing SCADA, ICS and other OT environments, I almost always get the feedback that cybersecurity isn’t required, because their systems are physically separated from the open Internet. This practice, referred to in ICS circles as the “airgap”, is the way ICS networks have been protected since the beginning of time; and truth be told, it’s been tremendously effective for decades. The problem is, the reality of the airgap began to disappear several years ago, and today is really just a myth.
Today, networks of all types are more connected than ever before. Gone are the days where only information technology (IT) networks are connected, completely separated from OT networks. OT networks are no longer islands unto themselves, cut off from the outside world. Technology trends such as the Internet of Things (IoT) have changed all of that. To gain business efficiencies and streamline operations, today’s manufacturing plants, field area networks, and other OT environments are connected to the outside world via wired and wireless communications – in multiple places throughout the system! As a result, these industrial environments are every bit as open to hackers and other cyber threats as their IT counterparts. The main difference, of course, is that most organizations have relatively weak cybersecurity controls in these environments because of the continued belief that an airgap segregates them from the outside world, thereby insulating them from cyber attacks. This naivety makes OT environments an easier target.
The authors of HAVEX certainly understand that OT environments are connected, since the method of transmission is via a downloadable Trojan installed on the websites of several ICS/SCADA manufacturers. What’s considered a very old trick in the IT world is still relatively new to those in OT.
It’s absolutely essential that organizations with ICS environments fully understand and embrace the fact that IT and OT are simply different environments within a single extended network. As such, cybersecurity needs to be implemented across both to produce a comprehensive security solution for the entire extended network. The most important way to securely embrace IoT is for IT and OT to work together as a team. By each relinquishing just a bit of control, IT can retain centralized control over the extended network – but with differentiated policies that recognize the specialized needs of OT environments.
We’ll never completely bulletproof our systems, but with comprehensive security solutions applied across the extended network that provide protection before, during, and after an attack, organizations can protect themselves from most of what’s out there. A significant step in the right direction is to understand that the airgap is gone forever; it’s time to protect our OT environments every bit as much as we protect our IT environments.
Industrial control systems is the term used to identify several types of control systems, including supervisory control and data acquisition (SCADA) systems, process control systems (PCSs), and other smaller control system types, such as programmable logic controllers (PLCs), used in critical infrastructure such as power plants, oil and gas pipelines, electrical power distribution, and manufacturing facilities.
Historically these control systems were kept separate from the corporate network. Because of this isolation they were traditionally difficult to break into because of their separation for health and safety reasons.
More recently, control systems may be running Windows or Linux, using the Internet Protocol (IP) to communicate, giving direct access to SCADA networks via the Internet. Wireless and Bluetooth capabilities allow remote management and diagnosis. These connections to the outside create a massive challenge from a security perspective for the following reasons: