Operational Technology (OT) refers to the hardware and software systems that control and monitor physical devices and processes in industries such as energy, manufacturing, transportation, and utilities. OT systems are often used in critical infrastructure and are increasingly connected to the internet, making them potential targets for hackers.

What Is OT Ransomware and Why Should You Care?

In recent years, there has been a sharp increase in cyber attacks targeting OT systems. In our recent 2023 Threat Report, we mapped out 57 cybersecurity incidents that had physical consequences out of 218 reported attacks. These events highlight the vulnerabilities of OT systems, the potential consequences of “successful” attacks, and most importantly, the fact that they are dramatically increasing each year.

OT hackers, also known as industrial control system (ICS) or SCADA (Supervisory Control and Data Acquisition) cyber attackers, typically aim to gain unauthorized access to OT networks and disrupt or manipulate critical processes. Their motivations may vary, including financial gain, espionage, activism, or sabotage.

Here are some general activities OT hackers are busy with these days:

OT hackers typically search for vulnerabilities in ICS and SCADA systems, such as outdated software, weak passwords, or insecure network configurations, as well as using open-source research to find exploits for these vulnerabilities in order to gain unauthorized access.

Finding and Exploiting OT System Vulnerabilities

Here’s an example of Hunting for ICS vulnerabilities by Cody Bernadry:

AI-Generated Malware Targeting OT Hardware

In the past, ICS hackers would require large teams to create the malware payloads that they intended to install once they hacked into the system. Most OT systems are fairly obscure when compared against common technology such as computers and smartphones, so finding hackers that are familiar with each OT system was the biggest obstacle. With the recent advent of AI that can write code, hackers can explain what they need in simple English, and then have the required code generated for them, ready for the attack.

Additionally, AI generated malware is much harder to catch, as it is considered clean when scanned by an IDS or malware detectors, since it is the first time that code is being used anywhere.

Here’s a clip from Cyber News that highlights some examples of using ChatGPT to generate malware, or simply recreating existing malware but with fresh code that can’t be detected as easily:

Social Engineering:

Sometimes, hackers don’t use any software to bypass all the safeguards, rather, they use the weakness of human nature to gain access.

Who would win:

• The most robust firewall and IDS ever created?
  or…
• A sweet mom with a crying baby in the background who just needs some help getting back into the system?Have a look:

This crying-baby social engineering hack shown in the video above is largely focused on getting IT credentials and info. The scope of this article is on OT hackers, so it is important to point out that most attacks on OT are initiated via the IT. So, it is totally expected that social engineering techniques focused on penetrating OT defenses would have a kill-chain that runs through the IT department.

Social Engineering Bus Hack:
As machinery and systems become more hardware and less software, does that negate the possibility of it being hacked? This hacker points out how he used knowledge combined with a unique hole puncher and thrown-out stacks of bus transfer tickets to “hack the system” and get free bus rides. Take a look:

Supply Chain Cyber Attacks:

Instead of engaging a target directly, hackers sometimes try to target an OT network indirectly by focusing on their supply chain of 3rd party vendors. All it takes is just one of many vendors to miss something to end up providing a “backdoor” to the entire OT network. By compromising the supply chain via 3rd parties, hackers can gain access to the targeted systems indirectly, in ways that are way more cumbersome to audit and prevent.

Here we have some examples of supply chain attacks, including an explanation of Target’s Customer Data Breach which was the result of hackers exploiting the air conditioning ICS because they had only used the free version of the malware software, and not the paid version. Once the HVAC system was hacked, the hackers used that access to install skimming software on each cash register’s credit card reader and recorded the credit card details of all customer transactions.

Have a look:

OT Ransomware: The Ultimate Goal

OT ransomware attacks are where hackers encrypt critical systems, and then demand a ransom (payment) for the decryption key which is needed to unlock everything. The kind of attacks have increasingly targeted OT systems because the “critical” aspects of their purpose are seen as applying pressure for the ransom to be paid.

The BBC did a short piece about a Norwegian company that suffered a costly ransomware attack. Have a look:

It’s important to note that the field of cybersecurity is dynamic, and new attack techniques and methods continuously emerge over time. Organizations that rely on OT systems should keep updated on the latest security best practices.

In conclusion, the activities of OT hackers pose a significant threat to operational technology systems in vital industries. The increasing number of cyber attacks targeting these systems emphasizes the vulnerabilities they face and the potential consequences of successful attacks. OT hackers often employ many other tactics than the ones mentioned above and are able to gain unauthorized access and disrupt critical processes. By understanding the tactics and activities of OT hackers, organizations can better posture their cyber defenses in order to protect their critical infrastructure and ensure the reliability and security of their operations in an increasingly interconnected world.

Real-World OT Ransomware Case Studies

Colonial Pipeline: Lessons from America’s Largest Fuel Disruption

In May 2021, the Colonial Pipeline—which supplies nearly half of the fuel to the U.S. East Coast—was forced to shut down after a ransomware attack compromised its IT systems. While the operational technology (OT) systems controlling fuel flow were not directly encrypted, the company proactively halted operations to prevent the attack from spreading, triggering the largest fuel disruption in U.S. history. Gas shortages rippled across multiple states, panic buying ensued, and the incident highlighted the cascading impact of a cyberattack on critical infrastructure.

The Colonial Pipeline attack exposed several key lessons for industrial organizations. First, IT-OT interdependencies mean that even attacks on corporate networks can halt physical operations if clear segmentation and response plans are lacking. Second, ransomware actors are now targeting critical infrastructure for financial and strategic gain, making proactive security measures essential. Finally, the incident underscores the need for secure remote access, network segmentation, and incident response planning—because when IT is compromised, OT resilience becomes the last line of defense.

Norsk Hydro: Manufacturing Resilience Under Attack

In March 2019, Norsk Hydro, one of the world’s largest aluminum producers, suffered a devastating ransomware attack that spread rapidly through its IT networks. The attack forced the company to halt or switch to manual operations across multiple plants and global facilities, significantly disrupting production. Despite the sudden impact, Norsk Hydro chose not to pay the ransom, instead relying on backups, strong incident response procedures, and transparent communication to recover operations.

The attack on Norsk Hydro highlights the critical importance of operational resilience in industrial environments. Effective segmentation between IT and OT networks, combined with manual fallback procedures, allowed the company to maintain essential functions while restoring its systems. Their response demonstrated that preparation, transparency, and a strong cybersecurity culture are as vital as the technologies themselves. The incident remains a benchmark for how manufacturers can respond to modern cyber threats without capitulating to attackers.

Water Treatment Facility Attacks: Critical Infrastructure at Risk

Cyberattacks on water treatment facilities have become a stark reminder of the vulnerabilities facing critical infrastructure. In 2021, a hacker gained remote access to a water treatment plant in Oldsmar, Florida, attempting to alter chemical levels in the drinking water to dangerous concentrations. Only the quick response of an operator prevented a potentially catastrophic public safety incident. Similar attacks worldwide, often targeting remote access points or outdated industrial control systems, demonstrate how even small facilities can become high-impact targets.

These incidents underscore the urgent need for robust cybersecurity in water and utility operations. Weak or unmonitored remote access, poor network segmentation, and reliance on legacy systems create an open door for attackers. Protecting water treatment infrastructure requires hardware-enforced remote access, continuous monitoring, and layered defenses to ensure that public health and safety are never left to chance.

Regulatory Frameworks and Compliance Requirements

As industrial organizations become increasingly connected, regulatory bodies are raising the bar for cybersecurity. Governments and industry authorities worldwide have issued standards, mandates, and best practices to help critical infrastructure operators strengthen their defenses. Compliance is not only a legal and contractual obligation but also a fundamental step toward reducing risk, protecting operations, and maintaining public trust.

From CISA in the United States to ENISA in Europe and NERC CIP for the energy sector, these frameworks establish the minimum expectations for securing operational technology (OT) environments. Compliance also ensures that your organization can respond effectively to audits, maintain certifications, and demonstrate due diligence in the event of a cyber incident.

Understanding Your Compliance Obligations

The first step toward meeting compliance requirements is knowing which regulations apply to your organization. Obligations may vary depending on your industry, geography, and the type of industrial systems you operate. Key areas often include:

• Access Control and Authentication – Ensuring that only authorized personnel can access critical OT systems.

• Network Segmentation and Monitoring – Isolating sensitive OT assets from IT networks and monitoring traffic for anomalies.

• Incident Response and Reporting – Preparing for and documenting responses to cyber incidents to meet regulatory reporting timelines.

• Data Privacy and Protection – Safeguarding operational and personal data in line with GDPR, CCPA, or sector-specific laws.

By understanding your compliance landscape and integrating it into your cybersecurity strategy, you reduce risk while avoiding costly penalties and reputational damage.

Implementing Security Controls

Implementing effective security controls is essential for protecting industrial and OT environments against evolving cyber threats. Unlike traditional IT systems, industrial control systems (ICS) and SCADA environments require tailored defenses that prioritize safety, uptime, and reliability. A layered approach—often referred to as defense in depth—ensures that if one control fails, others remain in place to mitigate risk.

Key security controls for industrial networks include:

• Network Segmentation – Isolate OT networks from IT and external connections to minimize attack surfaces.

• Strict Access Control – Implement role-based access, multi-factor authentication (MFA), and the principle of least privilege.

• Continuous Monitoring and Logging – Track network activity, identify anomalies, and enable rapid response to suspicious events.

• Patch and Vulnerability Management – Regularly update OT systems where feasible and mitigate risks for legacy or unpatchable devices.

• Secure Remote Access – Replace traditional VPNs and jump hosts with hardware-enforced or unidirectional access solutions.

• Backup and Recovery Plans – Maintain tested backups to ensure operational resilience in the event of an incident.

By implementing these controls in alignment with regulatory frameworks and industry best practices, organizations can significantly reduce their exposure to attacks while maintaining operational continuity.

Key Takeaways: Protecting Your OT Network from Ransomware

In conclusion, the activities of OT hackers pose a significant threat to operational technology systems in vital industries. The increasing number of cyber attacks targeting these systems emphasizes the vulnerabilities they face and the potential consequences of successful attacks. OT hackers often employ many other tactics than the ones mentioned above and are able to gain unauthorized access and disrupt critical processes. By understanding the tactics and activities of OT hackers, organizations can better posture their cyber defenses in order to protect their critical infrastructure and ensure the reliability and security of their operations in an increasingly interconnected world.