Strengthening Your Supply Chain: Proven OT and IIoT Cybersecurity Strategies

Imagine a smart factory that uses IIoT and OT devices to secure its network and monitor performance. The devices communicate over a secure, segmented network and use a monitoring platform to monitor device behavior.

One day, a normally low-traffic IIoT sensor starts behaving abnormally, transmitting data in bulk to an unknown external IP address. This sudden deviation from expected behavior triggers an alert. The OT monitoring solution sends the internal security and IT team, rolls back any unauthorized changes to the device, and blocks traffic to the external IP addresses. From here, the internal security team will conduct a forensic investigation and, if necessary, take additional mitigating actions.

Now, imagine if the manufacturer didn’t have a solution in place to protect their connected devices. If the IIoT sensor was transmitting data after hours or during a period of low staffing, or no one had noticed the anomalous behavior, then consequences could have rippled across the supply chain. A cyber attack could have halted production, causing missed deadlines, delayed orders, or compromised products. Alternatively, threat actors could have used their access to move laterally across the network and deploy ransomware, spreading the infection to downstream vendors and suppliers. 

Key OT Security Guidelines that Help Protect the Supply Chain 

Connected machinery requires a different approach to cybersecurity than traditional IT assets. OT environments are a mix of legacy and connected systems, many of which may run old, unsupported software. This unique blend of technologies creates a perfect target for malicious actors to spread malware, exfiltrate sensitive data, or grind production to a halt.

For example, in February 2023, Applied Materials, a semiconductor equipment manufacturer, announced financial losses of $250 million due to a ransomware attack against one of its suppliers. The cyberattack compromised sensitive employee information and disrupted MKS’s operations, affecting their ability to process orders, ship products, and provide services.

To effectively protect connected OT environments against cyber threats, manufacturers should leverage a purpose-built OT solution to identify and secure all connected OT and IIOT devices on the network. By doing so, they strengthen the security of both their network and the broader supply chain.

Network Monitoring and Anomaly Detection

A foundational first step for any OT security program is to identify all devices on the network and understand their behavior. Connected devices should only communicate with well-known IP addresses in well-understood ways. Other security controls, such as configuration control, will build upon understanding the specific parameters under which each device operates.

Generally, traditional passive scanners are not equipped to handle the complexity of IIoT and OT networks, as OT environments rely on specialized protocols (e.g., Modbus, DNP3, OPC UA) and proprietary systems. 

A purpose-built OT solution can parse OT communication protocols, identify and inventory all devices, and implement continuous monitoring to look for anomalous behavior. If a device begins behaving unexpectedly, the solution can alert the security team.

Implement Network Segmentation

Network segmentation is a well-understood IT concept that applies to OT environments, albeit with variations, although the end goal of both is the same: reduce the available attack service.

Targeted segmentation is a more granular approach, dividing devices into distinct segments, making securing OT/IIoT devices easier based on exploit vectors. For example, targeted segmentation may isolate IIoT sensors that interact with high-risk cloud applications to protect other devices on the network.

Implement Access Controls, Policy Management, and Device Configuration

As a best practice, limit access to critical manufacturing devices to authorized personnel who need access to devices to do their jobs. Beyond access management, policy management and configuration controls can help ensure devices operate within predefined constraints and adhere to various compliance and industry standards.

Part of understanding a device’s normal behavior is having a snapshot of a ‘known good’ configuration to identify any deviations from the baseline. Configuration drift in IIoT or OT systems, especially when it involves unauthorized or unexplained changes, can be a telltale indicator of compromise.

If routine monitoring identifies configuration drift, potentially due to unauthorized access, the OT solution can return the device to its known good state and alert on the suspicious behavior.

Leverage Threat and Incident Response

Like other industries that provide critical services, manufacturing has a low threshold for operational downtime, and outages can directly impact revenue and operations.

Threat intelligence feeds and continuous monitoring of OT systems allow manufacturers to quickly identify and respond to unusual activities, minimizing the risk of potential attacks and operational disruptions.

Often, speed is the most crucial factor when responding to a potential cyberattack in action, and the sooner security teams are alerted to suspicious activity, the sooner they can react. Ideally, manufacturers should use an OT solution that analyzes network traffic in real-time, allowing teams to immediately take mitigating actions.

Vulnerability Mitigation and Remediation

Unlike modern technologies, OT systems were designed to have longer lifespans, and older systems were not designed with cybersecurity in mind. The combination of legacy and modern technologies makes patching and mitigating vulnerabilities more complex than IT environments. To account for this unique environment, the National Institute of Standards & Technology (NIST) Guide to Operational Technology (OT) Security recommends leveraging compensating controls wherever possible.

Manufacturers can leverage an OT solution to use industry standards to identify, analyze, and rank critical vulnerabilities and provide targeted recommendations by surfacing the simplest actions to reduce risk.

Securing the Supply Chain Starts Before the Manufacturing Line

Manufacturers play a pivotal role in the global supply chain, transforming raw materials into finished goods and distributing products. They also play a critical role in securing the supply chain against disruptive cyber threats. That security depends not only on the security practices of the factory but also on the devices themselves – how frequently they’re patched, and how strategically they were procured with cybersecurity in mind.

While connected devices in operational technology (OT) environments have afforded manufacturers numerous efficiency improvements, optimizing production and automation, they also create unique cybersecurity challenges. Previously, OT environments were ‘offline,’ disconnected from traditional IT environments. Now, connected OT and Industrial Internet of Things (IIoT) devices are integrated alongside legacy systems—and they’re an attractive target for malicious actors seeking to overwhelm or halt production. A successful cyberattack against a manufacturer can easily impact the supply chain.

When manufacturers implement robust security strategies—including leveraging a purpose-built OT monitoring solution—to safeguard connected devices, they also improve the security and integrity of the broader supply chain.  Safeguarding the supply chain from cyberattacks requires manufacturers to implement proactive risk management and mitigation strategies to protect their OT environments and connected devices. By securing these critical systems, manufacturers can reduce the likelihood of disruptions and maintain operational resilience in the face of evolving cyber threats.

Asimily: The All-in-One security Solution for IIoT & OT

Asimily is a trusted partner for securing manufacturing OT and IoT. Our platform is designed to meet the unique needs of OT security and provides targeted protection and passive monitoring of your entire environment. 

We recently launched the free Asimily OT Security RFP Template. This template is an editable Word document that allows manufacturers to quickly and easily track which key features each vendor’s OT security solution has. Each feature has a different section in the template, making it clear which features each vendor has so teams can evaluate how they align with the organization’s needs.

Download your free Asimily OT Security RFP Template today.