The US Industrial Control System Computer Emergency Response Team (ICS CERT) has released an updated report regarding the inner workings of the TRITON / HatMan malware that affected Triconex Safety Instrumented Systems last year, at an unnamed plant (probably in Saudi Arabia as per multiple sources). It now appears that the malware is not a simple hack that was done by a single person but a was a carefully designed cyberweapon (probably developed by a large team of professionals who are very familiar with the inner workings of the Triconex Safety Instrumented System). It is unclear as to the motive of this effort, but most likely it is to cause malicious damage to a plant by disabling it’s Safety Instrumented System.
The malware affects Tricon safety controllers by modifying in-memory firmware, to add additional programming. The extra functionality allows an attacker to read/modify memory contents and execute arbitrary code on demand through receiving specially-crafted network packets. HatMan consists of two pieces: a PC-based component to communicate with the safety controller and a malicious binary component that is downloaded to the controller. Safety controllers are used in a large number of environments, and the capacity to disable, inhibit, or modify the ability of a process to fail safely could result in physical consequences. This report discusses the components and capabilities of the malware and some potential mitigations.
Full details of how the malware works are detailed in the report here.
ICS CERT is a part of the US Department of Homeland Security (DHS) and deals with cybersecurity issues related to Industrial Control and Safety Systems including but not limited to DCS, PLC, SCADA and SIS. In recent years, malicious code has become a big issue for owners and operators of industrial plants and this is one more instance of plant safety being compromised due to malware.