An entire US gas pipeline was shut down for two days due to a ransomware attack according to a recent report from the US Cybersecurity and Infrastructure Security Agency (CISA). The hackers sent a spear-phishing email to someone on the IT network that crossed over into the OT network and infected HMIs, data historians, and polling servers on the process control system. Although only one facility was hit, management shut down the whole pipeline for two days, resulting in loss of productivity and revenue to the pipeline, as well as to upstream production systems and downstream distribution networks.
This need not have happened. There is a simple remedy―isolate the OT network. They could have used Skkynet software on a DMZ to keep their firewalls closed and their gas pipeline system secure.
Using a DMZ
The first technical recommendation in the CISA report is to segment networks using a DMZ: “Implement and ensure robust Network Segmentation between IT and OT networks to limit the ability of adversaries to pivot to the OT network even if the IT network is compromised. Define a demilitarized zone (DMZ) that eliminates unregulated communication between the IT and OT networks.”
The easiest and most cost-effective way to pass production data securely through a DMZ is using DataHub tunnelling. Because it is secure by design, DataHub tunnelling can provide bidirectional data flow with no open inbound firewall ports, and no VPNs. The key is to access the data, not the network. This technology has been deployed in mission-critical systems worldwide for over 20 years, and was implemented recently in the TANAP project in which DataHub software was used to securely transmit process data from an 1800 km pipeline into a central control system through closed firewall ports.
Secure OT Assets
The second technical requirement recommended by CISA is to secure OT assets as much as possible. The report said, “Organize OT assets into logical zones by taking into account criticality, consequence, and operational necessity. Define acceptable communication conduits between the zones and deploy security controls to Filter Network Traffic and monitor communications between zones. Prohibit Industrial Control System (ICS) protocols from traversing the IT network.”
Again, DataHub tunnelling is a ready, off-the-shelf conduit for making the necessary connections. It provides secure, bidirectional real-time data mirroring between logical zones of OT assets, and from OT to IT. Data traverses the tunnel using the DHTP protocol, and can be converted to or from industrial protocols at either end.
Of course, the most secure system relies on sound planning and operational strategies in addition to strong technical and architectural solutions. The choice of software is one element of a larger picture. But in this case, simply using Skkynet IoT software would have prevented this gas pipeline shutdown altogether.