Kaspersky said it saw only a small increase in the percentage of industrial control system (ICS) computers targeted in 2021 compared to the previous year, but there was a more significant rise for certain types of threats.

Overall, Kaspersky blocked “malicious objects” on 39.6% of the ICS computers protected by its products, up from 38.6% in 2020. On the other hand, in the second half of 2021, the company observed attacks only against 31.4% of devices, the smallest of any six-month period since the start of 2020.

However, there were certain types of threats where the number of detections has been on an upwards trend in the past two years. This includes spyware (blocked on over 8.1% of devices compared to 5.6% in H1 2020), malicious scripts and phishing pages (9.3% up from 6.5%), and cryptocurrency miners (2.1% up from 0.9%).

In North America, nearly 20% of systems were targeted, roughly the same as in Western Europe, Kaspersky’s report shows. In comparison, the percentage of targeted systems exceeded 40% in many parts of Asia and even 50% in Africa and Southeast Asia.

The cybersecurity firm’s solutions blocked roughly 5,000 malware families and 20,000 malware variants on industrial systems in both the first and the second half of 2021. In terms of variants, this is roughly the same as in the previous two years. However, in terms of malware families, while there was no significant change in 2021 compared to 2020, the numbers are roughly double compared to 2019.

Looking at the industries housing the targeted devices, the building and automation sector was hit the most, followed by oil and gas, manufacturing, energy, engineering, and automotive manufacturing.

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“While overall, the threat types that find their way to ICS computers have remained relatively the same, we have seen a constant increase in the share of ICS computers facing malicious scripts and phishing pages along with Trojans, spyware and miners which would be normally delivered by the malicious scripts,” commented Kirill Kruglov, security expert at Kaspersky.

Kruglov added, “Crypto miners are generally overlooked as a significant threat, which is not a good approach. While the influence of miners on the office network may be insignificant, in the course of their work and distribution, they can lead to the denial of service for some components of the automated control system.”

Industrial systems from which the company collected data include SCADA servers, historians, OPC systems, engineering and operator workstations, HMIs, computers used to manage industrial networks, and devices that are used to develop industrial automation software.

Related: Increasing Number of Threat Groups Targeting OT Systems in North America

Related: Belarus, Ukraine Saw Largest Increase in ICS Attacks During H1 2021: Kaspersky

Related: Kaspersky Sees Rise in Ransomware Attacks on ICS Devices in Developed Countries

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.

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