Threats to industrial control systems are on the rise: More incidents involving ICS operators—organizations that use and maintain ICS as part of their operations—occurred in 2015 than any year prior.

And no wonder: ICS represents an increasingly diverse and extensively connected set of technologies. It controls and automates significant portions of our connected society, including power moving through the electrical grid, oil flowing through pipelines, travelers commuting on rail systems, and systems controlling pharmaceutical and food manufacturing.

According to Booz Allen, the number of incidents reported to US authorities rose by 17% in FY 2015. With 295 reported incidents, 2015 had the most reported incidents to date. And for the first time since ICS-CERT began tracking reported incidents in 2009, critical manufacturing experienced more incidents than the energy sector.

Spearphishing is the primary method of attack, with the number of attacks increasing by 160%—from 42 to 109—from FY 2014 to FY 2015.

Based on Booz’s analysis, new targets, including light rail operators, and new tactics, such as SCADA-access-as-a-Service (SAaaS) and ransomware against ICS, are likely to emerge or expand. For instance, in December 2015 alone, hackers used SCADA access to cause a blackout in Ukraine that affected 225,000 citizens, while that same month, US investigators revealed that an Iranian hacker had previously gained access to the Bowman Dam in New York through a SCADA system.

The report also uncovered that nation-state-backed groups are conducting sophisticated and widespread campaigns to steal operational data and establish footholds in ICS environments. Evidence of this is North Korea’s reconnaissance of light-rail operators in potential preparation for an ICS attack. Within the past eight months, North Korea has been tied to three separate reconnaissance attacks on South Korea’s light-rail operators. In each scenario, North Korea stole information pertaining to critical systems, such as speed and safety controls, traffic flow monitors and other central operating systems.

Safety, availability, protection of the environment, and process uptime are the primary drivers of ICS cybersecurity investments. Unfortunately, bad actors recognize the operational, economic and safety impacts attacks on ICS infrastructure can cause.

“Awareness of the risks associated with these systems is important, not just for the operational technology cybersecurity professionals responsible for securing these networks and devices but also for information technology professionals, organizational leaders, and regular employees,” Booz Allen noted in a threat briefing. “The impacts of attacks on ICS can be devastating. Attacks can cause extended operational halts to production and physical damage, and even jeopardize the safety of employees and customers. The attack surface for ICS is larger than just the ICS devices, equipment, and networks: It extends to all parts of an organization, including the extended supply chain.”