A Complete Guide to Critical Infrastructure Security

Critical infrastructure is the backbone of modern society… It’s the assets, systems, and networks our nation relies on for national security, economic growth, and public safety. With over 420 million cyber attacks on these essential services every year worldwide, securing critical infrastructure is one of the biggest challenges facing government agencies and private organizations. 

This article covers the best practices for securing critical infrastructure. It goes over why security is needed in the infrastructure sector, what the biggest threats are, and how to stay secure. It also covers key laws and regulations that critical infrastructure security systems must follow in the U.S. to stay compliant and working optimally.

Key Takeaways

• Critical infrastructure security protects vital systems like energy, water, healthcare, and transportation from cyber and physical threats. 
• Securing critical infrastructure requires public-private partnerships, continuous monitoring, employee training, and incident response planning to be best prepared against threats.
• Critical infrastructure security must be compliant with state and national laws and regulations, outlined by organizations like the EPA and CISA.

A Look at Critical Infrastructure 

To understand the scope of security needed for the critical infrastructure sector, it’s first important to understand what critical infrastructure is. 

The 16 Critical Infrastructure Sectors

The Presidential Policy Directive 21 (PPD-21) named 16 sectors of critical infrastructure that support American society and the economy. These sectors include everything from the energy that powers our homes to the healthcare systems that help us when we are sick. They create an interdependent system that is essential to national security. Many of these are “high-value” industries: They need to be protected because of their critical role in national security and the economy. The sectors include:

1. Energy
2. Water and Wastewater Systems
3. Transportation Systems
4. Communications
5. Information Technology
6. Healthcare and Public Health
7. Emergency Services
8. Food and Agriculture
9. Chemical
10. Critical Manufacturing
11. Defense Industrial Base
12. Financial Services
13. Nuclear Reactors, Materials, and Waste
14. Government Facilities
15. Commercial Facilities
16. Dams

Understanding the interdependencies between these critical infrastructure sectors is key to protecting them. For example, energy systems power water treatment plants, telecommunications networks enable financial transactions, and transportation systems deliver medical supplies to hospitals. The interconnectedness of this system means that protecting critical infrastructure requires a holistic approach that considers how threats can cascade across multiple sectors.

Ownership of these critical infrastructure sectors is split between public and private entities, with about 85% owned and operated by private companies (though this can vary by state). To maximize security, strong partnerships between government agencies and critical infrastructure owners are required to develop solutions that protect essential services while keeping operations running. 

High-Risk Sectors

Some sectors are more at risk than others. Their societal importance makes them a target for maximum disruption.

Energy (including grids, pipelines, and nuclear facilities) is one of the most critical sectors, making it a national priority. To secure against threats, we need to strengthen resilience, modernize the grid, and reduce vulnerabilities to keep the supply of energy reliable. These systems are most at risk for cyber attacks from nation-states, ransomware, and extremists due to vulnerable legacy operational technology.

Water and wastewater treatment services are critical for public health, serving over 300 million Americans. The industry manages aging infrastructure, making it more vulnerable to attacks. 

Healthcare is a prime target for criminals to disrupt services and steal patient data. Organizations manage life-critical systems and massive patient databases. Ransomware attacks can divert patients and delay critical treatments, impacting patient care and safety.

Financial services keep the economy running, processing trillions daily. They are vulnerable to attack from foreign nation-states that aim to disrupt the economy. Because this sector is intertwined with others, an attack could be devastating, affecting both economic stability and national security.

Transportation moves people and goods across highways, railways, airports, and shipping ports. More technology has both improved efficiency for the sector and also created new attack vectors. Disruption to transportation widely affects supply chains, emergency services, and economic activity.

Current Threat Landscape

The threat landscape for critical infrastructure is getting more intense, with attacks from foreign nation-states, cybercriminals, terrorist groups, lone attackers, and insider threats.

Cyber threats are growing fast. Nation-state sponsored advanced persistent threats (APTs) conduct long-term campaigns for access, using resources to develop zero-day exploits and custom malware for operational technology. Ransomware groups are also very dangerous, driven by profit and operating from safe havens, creating a criminal ecosystem that targets critical services from afar.

Physical threats range from deliberate attacks to natural ones, such as terrorism, shootings, sabotage, or natural disasters and extreme weather, with increasingly frequent and devastating hurricanes and floods in recent years causing more damage to critical infrastructure. 

Insider threats are unique, carried out by people with legitimate access who may act maliciously or unintentionally create vulnerabilities. Finally, supply chain vulnerabilities can allow attackers to compromise critical infrastructure by targeting suppliers, vendors, or service providers, introducing malicious code or unauthorized access through trusted relationships.

Notable Security Incidents

Recent events have taught us valuable lessons about the vulnerabilities in our critical infrastructure and the consequences of a successful attack. These events show we need comprehensive security and incident response.

Globally, the 2015 Ukraine power grid attack was the first confirmed cyber attack to cause a power outage, affecting around 225,000-230,000 people in the middle of winter. The sophisticated attack involved spear phishing emails to get initial access, reconnaissance, lateral movement through corporate networks, and direct manipulation of SCADA systems to open breakers and disconnect power generation. The attackers also targeted backup systems and communication networks to make the response more difficult.

In the U.S., several security incidents in 2021 revealed the real-world impacts of various threats against infrastructure. Firstly, in early February, a hacker attempted a cyberattack on a water treatment plant in Oldsmar, Florida. They got into the plant’s remote-access interface and tried to increase sodium-hydroxide levels from 100 ppm to 11,100 ppm… a concentration that would harm anyone drinking the treated water. The attack showed key vulnerabilities in the water and wastewater sector and could have been a public health disaster had it not been resolved quickly. 

Weeks later, a winter storm in Texas showed how insufficient weatherproofing and climateproofing can be devastating. Unusual temperatures and extreme weather caused energy infrastructure (e.g., wind turbines, pipelines, and power plants) to fail, and a large portion of the state’s privately-owned grid shut down. Approximately 4.5 million homes and businesses were without power for several days, and many people suffered serious illness or death as other services cascaded.

In May of 2021, the Colonial Pipeline ransomware attack showed how a cyber attack on energy infrastructure can have far-reaching economic and social impacts. The DarkSide ransomware group got into the company’s IT systems, and the company voluntarily shut down the pipeline network to prevent it from spreading to operational systems. This precautionary measure caused fuel shortages across the Eastern United States for nearly a week. This resulted in price increases and panic buying that affected millions of Americans.

Most recently, this year, there was a shooting at the Atlanta Centers for Disease Control and Prevention (CDC) campus in a literal and ideological attack against public health. A man motivated by health misinformation fired over 500 rounds into the campus, killing a responding police officer and inciting fear among public health professionals around the country. 

Healthcare attacks (both physical and cyber) are becoming more common, with major health systems experiencing significant disruptions to patient care. These attacks force hospitals to cancel elective procedures, divert emergency patients to other facilities, and resort to manual record-keeping systems that slow treatment and increase the risk of medical errors.

Looking at these incidents, we see common patterns in attacker techniques and defender vulnerabilities. Attackers often spend a lot of time doing reconnaissance before launching the final attack, so improved monitoring and detection could have identified the threat before it caused significant damage.

Security Best Practices 

Full Spectrum Critical Infrastructure Protection

Critical infrastructure protection requires a full-spectrum security program. These programs are built on the principle of layering both cyber and physical defenses, balancing between security requirements and the operational reliability and efficiency of the infrastructure.

Strategic Risk Assessments and Investment Prioritization

Security investments for critical infrastructure must be prioritized based on continuous risk assessments. These assessments weigh the probability and impact of various threat scenarios.

Given the nature of critical infrastructure, the impact of threats like cyber attacks, mass shootings, or terrorist attacks is severe and far-reaching. They can impact public safety, cause significant economic disruption, threaten national security, and cause catastrophic environmental damage. By quantifying and ranking these risks, resources can be allocated to address the most critical vulnerabilities and threats first.

Advanced Physical Security

Advanced physical security is a must for critical infrastructure protection, complementing robust cyber defenses. Facilities must deploy modern physical security technologies strategically, including multi-layered access control systems, sophisticated surveillance with AI-powered features like gun detection and anomaly recognition, perimeter hardening via reinforced barriers, and integrated alarm systems. These technologies must be connected through physical security automation platforms. Automation (like automatically locking down sections, deploying barriers, or alerting first responders based on live sensor data) speeds up response times to intrusions, suspicious activities, or physical threats, minimizes the window of vulnerability, and enhances overall site resilience.

Cyber Defense

Cyber defense is part of the protection and relies heavily on advanced network security principles. This includes deep network segmentation, which limits the lateral movement of attackers and full adoption of Zero-Trust security principles. Zero-Trust means strict verification for every user, device, and application trying to access any resource, regardless of whether the entity is inside or outside the network perimeter. Access control systems are further enhanced through multi-factor authentication (MFA) and sophisticated privileged access management (PAM) solutions that severely restrict and monitor interactions with the most critical and sensitive control systems.

Continuous Monitoring and Service Resilience

Real-time visibility into the security status of the infrastructure is maintained through continuous monitoring. This can be done with Security Information and Event Management (SIEM) systems for the Information Technology (IT) environment, supplemented by specialized monitoring and anomaly detection solutions.

Monitoring is key to catching physical threats before they escalate. Unfortunately, monitoring CCTV footage can cause fatigue and lead to missed threats. Object recognition technology has been developed as a solution to this problem, running 24/7 and programmed to scan live footage for weapons proactively. This allows security personnel to focus on other aspects of security while still getting alerted to any detections. Only when a detection is verified does a response get initiated.

Beyond defense, service resilience is ensured through comprehensive backup and disaster recovery plans. These plans ensure rapid, orderly service restoration after an incident. Crucially, these resilience measures are not static; they must be regularly and rigorously tested through realistic simulations to validate their effectiveness, identify weaknesses and ensure all recovery objectives can be met within acceptable timeframes.

Structured and Adaptive Incident Response

A highly structured and adaptive incident response plan is required to manage and recover from security events. These plans detail precise procedures for the entire incident lifecycle: detection, in-depth analysis, containment, eradication, and final recovery. The plan must be tailored to the specific critical infrastructure in question, including kinetic effects and the risk of rapid, cascading failures across interconnected systems.

The incident response team must be multi-disciplinary, using expertise from security, IT, OT/ICS engineering, legal counsel, public relations (PR), and executive management. Pre-established relationships with external entities like law enforcement, government agencies, and specialized third-party security firms must be in place to facilitate rapid and coordinated support.

Containment is complex and requires a delicate balance: Preventing further system damage while maintaining essential operational functionality. This may involve sophisticated isolation techniques for compromised segments or the rapid deployment of manual, physical controls to sustain critical services.

Throughout the entire process, well-defined and rigorously adhered-to communication protocols are critical to ensure timely, accurate, and consistent updates are provided both internally to stakeholders and externally to the public and regulatory bodies. Critical infrastructure facilities should have mass notification systems and emergency notification systems to quickly disseminate information and instructions across the organization and to the public if necessary.

After an incident, mandatory post-incident activities must be conducted to capture all lessons learned and implement concrete improvements across all security domains. The recovery phase should be prioritized, focusing first on restoring essential, verified-clean services to full operational status.

The Human Element: Training, Awareness, and Culture

The human element is key as employees are the best line of defense and a primary attack vector for attackers. A comprehensive and multi-faceted training program is non-negotiable. This training must cover a wide range of topics, including advanced cybersecurity practices (e.g., identifying phishing, recognizing social engineering tactics), strict adherence to physical security protocols (e.g., access control procedures, immediate reporting of suspicious activity, and use of security tools), and role-specific security duties.

Security awareness programs must be continuous, dynamic, and regularly updated to address new threats and evolving attacker methods. A culture of security requires robust whistleblower protection policies. This means that employees can feel safe to report any security concerns, vulnerabilities, or suspicious activity without any fear of retribution or retaliation. This strengthens the organization’s proactive defense posture.

Public-Private Partnerships

Security for critical infrastructure requires strong partnerships between government agencies and the private sector. These partnerships are key to developing comprehensive security plans through coordinated response, shared information, and each sector’s unique strengths to address complex security challenges.

Public-Private Collaboration Paths:

• Information Sharing and Analysis Centers (ISACs): These are essential for sector-specific sharing of threat intelligence, vulnerability data, and security best practices among critical infrastructure operators. They act as trusted intermediaries, facilitating communication between the government and private sector, sharing classified threat information with cleared partners while protecting sensitive business data and competitive relationships.
• Joint Cybersecurity Initiatives: These bring together government expertise in threat intelligence and incident response with private sector operational knowledge and resources. Activities may include joint exercises, collaborative research and delivery (R&D), and coordinated response to major incidents. The goal is to leverage the combined strengths of both sectors, prevent duplication of effort, and ensure a unified approach to shared security problems.
• Cost-Sharing Programs: Federal funding is available through these programs to help private organizations fund security improvements. Some security investments (while providing significant public safety and national security benefits) may not have immediate commercial returns. Funding can be used for vulnerability assessments, technology deployment, training, or R&D.
• Research and Development Partnerships: Partnerships between government labs, universities, and private companies get new security solutions to market faster and ensure they meet operational needs. The government provides funding and research facilities, while private partners provide operational expertise and commercialization capabilities.
• Standards Development: This brings together government agencies, private sector entities, and technical experts to develop consensus-based security standards. These voluntary guidelines allow organizations to improve their security more efficiently. Common standards improve information sharing and interoperability across the industry while reducing compliance costs.

Emerging Technologies and Future Challenges

Technology is moving fast and is a double-edged sword for critical infrastructure security, offering new tools for defense and new ways for attackers to attack. Security programs must adapt.

Key Technological Impacts:

• Artificial Intelligence (AI) and Machine Learning (ML): AI and ML can help with threat detection and incident response in complex environments. They can analyze massive amounts of network traffic and find subtle, sophisticated attack patterns, adapt to new techniques, and reduce false positives in traditional signature-based systems.
• Internet of Things (IoT) Proliferation: More IoT devices in critical infrastructure means more new, often vulnerable endpoints. These devices have limited built-in security and are hard to patch at scale, which means no comprehensive visibility and management. Many IoT devices are commodities, so it’s hard to implement robust security controls.
• 5G Network Deployment: 5G will bring transformative capabilities like ultra-low latency for industrial control systems and massive sensor network connectivity. But it’s more complex and software-defined, so there are new vulnerabilities. The global supply chain for 5G equipment raises concerns about nation-state actors introducing backdoors or weaknesses.
• Smart City Initiatives: Integrating multiple critical infrastructure systems through shared networks and data platforms improves efficiency but creates complex interdependencies. This convergence means a security incident in one area can have severe, cascading effects across multiple city services.
• Cloud Computing Adoption: Moving critical infrastructure operations to the cloud brings scalability and cost benefits, but new security complexities. Operators must thoroughly vet Cloud Service Provider (CSP) security capabilities and fully understand the shared responsibility security model. Hybrid architectures, blending on-premises and cloud resources, require careful design to prevent vulnerabilities at the integration points.

Government Agencies and Frameworks

Critical Infrastructure Protection in the U.S.

Protecting the nation’s critical infrastructure is important because its disruption or destruction would have a debilitating impact on national security, economic function, public health, or safety, or any combination thereof. It’s a complex and ongoing priority for the federal government. This effort includes multiple sectors and jurisdictions, involving many federal agencies, private industry, and state and local partners to ensure national security and resilience against cyber and physical threats.

CISA’s Central Role

The Cybersecurity and Infrastructure Security Agency (CISA) was established by the Department of Homeland Security (DHS) in 2018 and is the national lead for this mission. CISA’s main responsibility is to manage and reduce systemic risk to the nation’s cyber and physical infrastructure. This means working proactively with the owners and operators of critical assets, often in the private sector. CISA’s core services include providing timely and actionable threat intelligence, assessment and advisory services, and technical assistance and response support during and after security incidents. CISA also works closely with standard-setting bodies like the National Institute of Standards and Technology (NIST) to promote and facilitate the adoption of strong cybersecurity standards and best practices across all critical infrastructure sectors.

Oversight and Inter-Agency Coordination

While CISA is the operational lead, DHS has overall responsibility for the government-wide effort. DHS coordinates the activities of all relevant federal departments and agencies to ensure a unified federal approach. This coordination extends down to a formalized partnership with state, local, tribal, and territorial governments, recognizing that these jurisdictions are the first responders and often have direct oversight of non-federally owned critical assets. This broad collaborative framework for security and resilience is outlined in the National Infrastructure Protection Plan (NIPP), which provides the strategic context for how government and the private sector can work together to manage risk.

Standards and Policies

A key part of the national strategy is the development and voluntary adoption of common cybersecurity best practices. NIST plays a big role here through the creation of foundational resources like the widely used NIST Cybersecurity Framework (CSF). This framework uses a risk-based approach to improving an organization’s security posture, organized around five core functions: Identify, Protect, Detect, Respond, and Recover. It’s voluntary, so it can be adopted across many sectors, accommodating varying levels of maturity and regulatory requirements.

High-level policy direction comes from the Executive Branch. Presidential directives such as Presidential Policy Directive 21 (PPD-21), Critical Infrastructure Security and Resilience, set the overall strategic goals and emphasize the importance of public-private partnerships as the foundation of national security. More recent executive orders and national security memorandums have continued to raise the bar for cybersecurity, especially for federal information systems and the systems supporting critical infrastructure, often mandating specific actions such as software bill of materials (SBOM) requirements and cloud security enhancements.

Global Security and Resilience

The threats to critical infrastructure are global. International cooperation is not just nice to have; it’s necessary. The federal effort includes robust engagement with other nations and international organizations. This is important for global information sharing on emerging threats, coordinating responses to cross-border cyber incidents, and harmonizing security standards to ensure collective resilience against state and non-state actors operating globally.

Regulatory Compliance

The critical infrastructure sectors face a growing regulatory environment to meet minimum security standards and promote information sharing about threats and vulnerabilities. These requirements vary by sector and often involve multiple overlapping jurisdictions and authorities.

The NERC’s CIP standards require mandatory cybersecurity for bulk electric system operators. These standards require utility companies to identify critical cyber assets, implement protective measures, maintain security policies and procedures, and report security incidents to relevant authorities.

The TSA has issued security directives for pipeline operators and other transportation systems following high-profile attacks on energy infrastructure. These directives require operators to implement specific cybersecurity measures, report incidents to federal authorities, and designate a cybersecurity coordinator to interface with government agencies. The EPA regulates water and wastewater treatment facilities under various environmental policies and guidelines, including security assessments and emergency response planning. The America’s Water Infrastructure Act of 2018 added to these requirements by requiring risk and resilience assessments and emergency response plans for water systems serving more than 3,300 people.

Healthcare sector compliance involves multiple regulatory frameworks, including HIPAA for patient data protection and FDA guidelines for medical device cybersecurity. Health organizations must balance security requirements with the need to have immediate access to life-critical systems and patient information.

State and local regulations add to federal requirements and often impose additional obligations on critical infrastructure operators within their jurisdictions. These regulations may cover emergency preparedness, environmental protection, public safety, or other issues that impact infrastructure security and resilience.

Summary

Critical infrastructure keeps society healthy and happy. It allows us to live our daily lives, from drinking clean tap water and cooking food, to getting to work and back home safely. Because it’s so important, it can easily become the target for attacks.

Critical infrastructure security is crucial to American society. By having robust, multi-layered protocols and a security-aware culture, critical infrastructure owners and operators can protect their assets from cyber attacks, physical threats, and other risks. These proactive measures are necessary for the success of the nation’s critical infrastructure sectors, homeland security, and the economic well-being of communities across the country.

Omnilert offers a range of security solutions for critical infrastructure, including mass and emergency notification systems that can support facilities’ communications needs, security workflow automation, and Gun Detection technology.

Frequently Asked Questions (FAQs)