In 2024, the security of OT (Operational Technology) and ICS (Industrial Control Systems) networks became a critical point for all manufacturing and infrastructure companies. With the increasing digitalization of plants, the boundaries between IT and OT are becoming increasingly thin, opening up new attack surfaces. But what is OT security really? And why is it a top priority today for business continuity and the protection of industrial processes?

In this guide, designed for IT Managers, production managers and CEOs of industrial SMEs, we analyze risks, technologies, regulations and strategies to defend industrial assets in the current environment.

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What is OT security and how is it different from IT security

OT technologies include all physical and digital systems that monitor, control and automate industrial processes: PLC, SCADA, sensors, actuators, HMI. ICS (Industrial Control Systems) are the coordinated set of these devices.

Unlike IT security — focused on data, users and applications — OT security has unique characteristics and critical issues.

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The main differences between OT and IT security:

• Different objectives: IT focuses on confidentiality and data integrity; OT on business continuity and availability.

• Legacy technologies: OT uses old industrial systems that cannot be easily upgraded.

• Real-time: Many OT applications cannot tolerate downtime or delays.

• Apparent isolation: OT is often thought of as isolated, but integration with ERP, cloud and IIoT belies this illusion.

In short, OT is the weak link in industrial digital transformation. Protecting it requires specific approaches and tools.

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The 5 most common threats against ICS and industrial networks in 2024

With the evolution of cyber attacks, OT networks have also been targeted by malicious actors, from ransomware groups to nation-states.

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Here are the most common threats detected in 2023/2024:

1. OT-aware ransomware: malware that blocks production lines and encrypts operational data.

2. Insecure remote access: connections from third-party vendors and technicians without adequate MFA or VPN.

3. Absence of segmentation: OT and IT communicate freely, encouraging lateral movements of attackers.

4. PLC and SCADA tampering: malware such as TRITON or INDUSTROYER shows that even controllers can be sabotaged.

5. Human error and industrial phishing: HMI operators are often poorly trained and can fall into social traps.

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These threats are constantly growing and, if left unaddressed, can cause:

• Prolonged plant stoppages

• Physical damage

• Alteration of industrial processes

• Loss of sensitive data or intellectual property

• Penalties for non-compliance (e.g. NIS2)

Understanding these threats is the first step in addressing them with an effective defense plan.

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Best Practices for Effectively Protecting the OT Environment

Implementing an OT security strategy requires a mix of technologies, processes, and company culture. Protection cannot be limited to the installation of a firewall, but must involve the entire life cycle of the industrial process.

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Here are the top recommended best practices:

• Asset inventory and automatic discovery: know exactly which devices are connected to the network.

• Network segmentation: strictly separate IT and OT, introducing DMZ zones and industrial firewalls.

• OT behavioral monitoring: install ICS-specific IDS/IPS (e.g. Nozomi, Claroty) that detect anomalies without interfering.

• Access control and MFA: restrict access to critical devices and use strong authentication.

• Backup and disaster recovery: Create regular copies of PLC configurations and HMI data.

• Training of operational personnel: phishing simulations and basic policies (e.g. blocking inactive consoles, using secure USB sticks).

• Controlled patch management: apply firmware updates in a planned and tested manner, to avoid instability.

Adopting these good practices makes it possible to prevent the most common incidents and to respond more quickly in the event of an attack.

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How ArcGuard Can Help You — The Complete OT Security Solution

Many industrial SMEs do not have an internal team specialized in OT security. That's why ArcGuard offers a vertical service, specifically designed for industrial environments.

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The OT solutions offered by ArcGuard include:

• Technical assessment and OT gap analysis

• Segmentation and security of the OT network

• SCADA and PLC device protection

• 24-hour continuous monitoring through Security Operation Center (SOC)

• Attack simulations and training for industrial operators

• Compliance support (NIS2, ISO/IEC 62443, IEC 27001)

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All solutions are modular and adapted to the size of the plant and the level of cyber maturity of the individual company. No “one size fits all” package, but tailor-made projects, from the first assessment to full protection.

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In 2024, OT security can no longer be ignored. With the expansion of Industry 4.0 and increasing regulatory pressure, every industrial company — large or small — must face the vulnerabilities of its ICS systems. Investing today in assessment, segmentation, training and monitoring means preventing economic, reputational and legal damage tomorrow.

Do you want to know how exposed your production plant is?

ArcGuard offers you a free OT Security Assessment to identify hidden risks in your industrial network. Request it now → https://www.arcguard.it/en/contatti