Why Singapore’s critical infrastructure needs stronger OT defences

Digitalisation is transforming operational technology (OT), turning once-isolated systems into connected ecosystems that deliver greater efficiency, visibility and resilience. OT encompasses the systems that monitor and control physical processes, including industrial control systems, building automation, transport networks and energy infrastructure – many of which underpin critical services and national infrastructure. AI is reshaping the threat landscape , letting adversaries launch attacks faster and at greater scale. Sophisticated actors are using advanced capabilities to probe, penetrate and disrupt systems, making OT cyber security no longer just a technical concern but a strategic priority for organisations and governments alike. As smart infrastructure and production floors become more interconnected, those actors are targeting OT environments and critical infrastructure to disrupt operations and undermine resilience. A growing need for cyber resilience For organisations running OT environments, the challenges are evolving quickly. Many industrial systems were designed decades ago and prioritised reliability and safety above all else – long before today’s complex threat environment. At the same time, the integration of modern technologies such as cloud connectivity, remote operations, artificial intelligence and data-driven industrial applications, while opening up new opportunities, significantly expands the attack surface. Escalating activity by cyber criminals, hacktivist groups and state-sponsored threat actors against essential services worldwide – including power, energy, water and infrastructure – underscores a critical reality: sophisticated intrusions can severely affect public safety and operational continuity. As Josephine Teo, Singapore's minister for digital development and information, said at the Operation Cyber Guardian engagement event for cyber defenders in February 2026, such attacks are not theoretical. She pointed to US authorities’ report that an advanced persistent threat (APT) actor had infiltrated critical infrastructure across several American sectors, and to a sophisticated cyber attack on Poland's power grid in December 2025 . These persistent threats show that cyber security is not merely an IT concern, but a foundation for the operational resilience of societies and nations. Addressing the risks calls for a comprehensive, proactive approach spanning the full lifecycle of industrial systems – from initial design and deployment through to operation, maintenance and eventual modernisation. Organisations must adopt layered security strategies, strengthen network segmentation, improve visibility into OT environments and apply zero-trust principles that continuously verify access to critical assets. A critical first step is achieving comprehensive asset and vulnerability transparency. For asset owners and operators, that means maintaining a clear and up-to-date picture of every connected device, software version and potential vulnerability across the OT estate. That level of visibility lets organisations prioritise remediation, plan the replacement of end-of-life and end-of-support systems, and reduce their overall attack surface. Ensuring the continuous, safe and reliable operation of industrial systems demands an integrated and forward-looking approach to cyber resilience, making it an indispensable cornerstone of modern OT strategy. The high stakes of OT security The stakes could not be higher. Consider the ripple effects of a cyber attack that halts production at a major manufacturing plant, causing supply chain disruption and economic losses. Or the public safety implications when a sophisticated intrusion compromises a vital utility, leaving communities without power or clean water. These are not hypothetical scenarios; they are increasingly common threats that underscore the urgent need for a robust, integrated approach to OT cyber security. Conversely, organisations that have invested in comprehensive OT security frameworks – sharing threat intelligence, adopting advanced anomaly detection and building cross-functional security teams – have proved remarkably resilient. Their ability to detect, respond to and recover from incidents swiftly protects not only their own operations but also the essential services we all rely on. Effective OT cyber security is not merely about deploying technology; it is about cultivating a resilient ecosystem in which preparedness and rapid response are paramount. At Siemens, cyber security is built into how our industrial and OT systems are designed, developed and maintained. We work closely with customers to strengthen OT visibility, identify and manage vulnerabilities, implement secure architectures and improve resilience across the operational lifecycle. Effective OT cyber security is a collective endeavour, and collaboration across the ecosystem is needed to establish robust standards and contribute to national resilience. Beyond technology, a holistic approach is essential – one that builds trust through transparency, continuous improvement and collaboration. The Cyber Trust Mark is a certification programme run by the Cyber Security Agency of Singapore (CSA) to encourage organisations to meet cyber security benchmarks aligned to their risk profile. It has been expanded to cover areas such as cloud and OT environments , helping organisations strengthen cyber resilience through recognised best practices. Siemens Singapore’s ambition to achieve tier-five (advocate) certification by the end of 2027 reflects our commitment to advancing cyber security excellence and supporting Singapore's broader resilience objectives. One team against a common threat OT cyber threats are changing at an unprecedented pace, with attacks on critical infrastructure growing more frequent, sophisticated and persistent. That demands we make active use of advanced technology to build more intelligent and resilient defences. As a participant in the recent Operational Technology Cybersecurity Expert Panel (OTCEP) Forum organised by CSA , we contributed practical insights to help strengthen OT cyber security across Singapore's critical sectors. As Singapore advances its digitalisation journey, protecting OT environments will be vital to safeguarding essential services, maintaining public trust and supporting sustainable growth. Together, we can build a safer and more resilient OT cyber ecosystem. Tulasidharan Mudiliar is global cyber security portfolio growth manager at Siemens.