Cyber Defense Strategies for Mass Transportation Networks

Every day, billions of people depend on subways, buses, airlines, and smart mobility platforms to keep cities moving. But as these systems become smarter and more connected, they also become more vulnerable. A single cyberattack can now paralyze entire transit networks, halting trains, grounding flights, and stranding millions.  On one hand, the digitization of mass transportation networks improves the quality of service by enabling optimization, safety, efficiency, and user convenience. On the flip side, transportation networks that rely heavily on digital systems also have significantly expanded attack surfaces across both IT and OT domains.

Threat actors, ranging from ransomware gangs to nation-state Advanced Persistent Threat (APT) groups, have learned to exploit the complex dependencies within transportation infrastructure. Hackers determined to cause chaos and extort ransom from critical transportation systems can now more easily figure out how to attack everything from signaling systems and SCADA controllers to smart fare payment systems and mobile transit apps.

This is not just about leaking data or damaging the company's reputation. Mass transit systems are relied upon by billions around the globe, every single day. Hackers recognize how important these systems are and, like other critical industries such as energy, government, and healthcare, seek to leverage any weaknesses they can find to fulfill their motivations, whether financial or political.

How Threat Actors Breach Transit Systems?

Attacks targeting mass transit today often begin through traditional vectors like phishing or credential stuffing but then pivot rapidly to target operational systems. For example, the breach of a transit organization’s vendor’s email account could grant access to the transport system’s backend credentials for fare systems or software updates.

In many cases, the initial intrusion point is surprisingly trivial. It could be an unpatched Windows system at a check-in kiosk, a default password on a ticketing validator, or a forgotten API key embedded in a mobile app. Once inside the network, however, hackers will often move laterally into critical OT systems such as train signaling or platform door control. At this stage, the attack becomes a high-impact threat because the transit organization's operations cannot continue without these critical systems.

A lot of the time, attacks against the transit sector leverage supply chain attacks. Indeed, a March 2025 study on the threat landscape for the global logistics and transportation industry found that 64.33% of threats aimed to disrupt the supply chain. The nature of these attacks means that even minor breaches can ripple throughout the entire industry, resulting in significant disruptions. 

In September 2025, check-in kiosks went dark across major European airports when a cyberattack hit Collins Aerospace, a key software vendor. Travelers stood in lines for hours, flights were delayed, and ground crews had no digital systems to fall back on. One breach at a vendor rippled across a continent.

Another recent example of this was the supply chain cyberattack against LNER, a UK train operator. In this hack, sensitive information was accessed through the breach of a third-party vendor. This attack, unlike the Collins Aerospace one, did not halt operations; however, it did put customer data at risk.

Cyberattacks against transit organizations can take many forms. As noted, hackers often target supply chain vendors, but this is not the only way. Attackers also target organizations directly, as in the 2023 cyberattack on DP World Australia, which disrupted five major ports. Hackers will also seek to incite fear with their hacks. For example, in September 2024, a cyberattack disrupted public Wi-Fi services at 19 major railway stations in the UK. In addition to this, customers attempting to log in were instead confronted by alarming messages referencing terror attacks.

As these incidents show, attackers don’t need to breach the train itself; they only need to compromise what keeps the system running. That’s why defense strategies must evolve just as quickly.

Building Resilient Transit Defenses

Transportation organizations that are serious about protecting these environments, which every transportation organization should be, must invest in multiple strategic layers to prevent data compromise, network shutdowns, and reputational damage. First, these organizations must treat IT and OT convergence not just as a technical challenge, but as a governance issue. Many transit agencies still operate these domains in distinct silos, leading to fragmented risk management and missed detections. Attacks against transportation networks are especially impactful if network segmentation has not been properly implemented, in which case a single system going down does not affect the others, leaving the overall network less susceptible to widespread damage. 

Beyond this, real-time monitoring and anomaly detection are critical for protecting these networks. Behavioral analytics tuned to industrial protocols (such as Modbus, DNP3, or proprietary signaling telemetry) can detect command injection attacks or unexpected lateral movement events that would otherwise go undetected by standard IT-focused tools. In fact, passive monitoring of CAN bus traffic on trams or buses can detect spoofing attempts early, often before passengers or operators even notice something’s wrong.

Often, a significant issue limiting transportation companies’ ability to implement cyber defenses is staffing limitations. Transit companies may struggle to recruit and retain cyber talent due to compensation limitations and legacy technology environments. One mitigation strategy in this case is for these organizations to outsource top-tier and higher-level detection and response to Managed Security Service Providers (MSSPs) or Managed Detection and Response (MDR) providers, while keeping more strategic incident response and OT oversight in-house. For example, a unified Security Operations Center (SOC) team is essential. At a minimum, transit organizations should staff a fusion team that continuously monitors cyber threats across different departments or systems.

Practice and Prepare: Why Simulation Is as Important as Prevention?

It is impossible to completely prevent cyberattacks. This is true in any sector. The best any organization can do is to have strong defenses in place from the start. Second, organizations should be well prepared in the event of an attack. To do this, transportation sector security teams should regularly conduct tabletop exercises to simulate realistic cross-domain cyberattacks. 

These simulations should follow the progression of typical transportation attacks. That is, they should begin with phishing or physical access, as most hacks do, then progress to access to payment systems, and finally culminate in disruptions of critical systems such as signaling and train schedules. These exercises must include in-depth communication plans with city authorities, public relations, and, if the scenario is significant, law enforcement or intelligence agencies. These exercises should help security teams, operational staff, and executives know exactly what to do and what to say in the event of a cyberattack.

Organizations should also always be prepared for a successful cyberattack. Part of this preparation includes developing ransomware-specific playbooks that provide detailed plans for offline backups of OT configurations and emergency fallback modes for signaling systems. Some transit systems have been forced to switch to paper tickets or manual switch operations due to ransomware attacks. This is a clear sign that even digital contingency planning must account for analog fallbacks.

The Policy Backbone Behind Transit Security

From a policy perspective, transportation companies and systems can look to specific frameworks to develop cybersecurity and data best practices. For example, organizations should consult NIST’s Cybersecurity Framework, IEC 62443 for industrial control system security, and the TSA’s Surface Transportation Security Directives, which now include cybersecurity mandates.

Additionally, sharing threat intelligence through Information Sharing and Analysis Centers (ISACs), such as the Public Transportation ISAC, is equally essential for proactively staying ahead of and being prepared for emerging threats. ISACs collect and disseminate threat intelligence to help members understand the threat landscape and implement actionable mitigation strategies.

Overall, by staying up to date with mandated cybersecurity policies and participating in optional best practices implemented by not-for-profit organizations (such as ISACs), transit organizations can be sure to stay ahead of threat actors who are always seeking to attack and undermine.

Transportation: A Critical and Rapidly Evolving Area of Concern

A train operator getting hacked and having their customers’ credentials leaked may seem like just “another” data breach, like the others that occur every single week. Yet this kind of breach not only puts customers at risk and therefore damages the company’s reputation but also shows the organization's weakness to begin with. If hackers can gain access to customer information, they most likely can also gain access to critical operational systems.

Imagine the impact hackers could cause. Major cities that run on public transport, with millions of people commuting every day, could be brought to a standstill. Traffic lights could be disrupted, subways halted, and airline and marine traffic navigation disrupted. These risks could easily bleed into impacting not just the profits of transportation companies, but also the safety and livelihood of people.

For this reason, it is critical to recognize the responsibility transit organizations hold. They must consider the large-scale impacts that could occur from their weak cyber defenses. Above all, they must prepare to handle cyberattacks so they can return to operation as quickly as possible and minimize damage.

Protecting mass transit networks isn’t just a cybersecurity issue; it’s a public safety imperative. Every delayed train or grounded flight after a breach chips away at public trust and national resilience. The next major transit cyberattack won’t just affect machines. It will affect people.