Safeguarding GPS and GNSS Systems Against Cyber Threats

Global Navigation Satellite Systems (GNSS), notably the Global Positioning System (GPS), have transformed how we navigate and operate in the modern world. From guiding vehicles to facilitating precision timing for critical infrastructure, GNSS plays a pivotal role in various sectors. However, the increasing reliance on these systems has also exposed them to a growing array of cyber threats. Protecting GPS and GNSS systems from cyber vulnerabilities is imperative to ensure their continued reliability and resilience.

The Critical Role of GNSS Systems

GNSS systems have become the backbone of numerous applications, spanning transportation, telecommunications, agriculture, defense, and more. They provide accurate positioning, navigation, and timing (PNT) data that underpin essential functions such as:

• Navigation: GNSS enables precise positioning for maritime, aviation, and land-based transportation systems, enhancing safety and efficiency.
• Timing Synchronization: GNSS-derived timing signals are critical for synchronizing telecommunications networks, financial transactions, power grid operations, and scientific experiments.
• Surveying and Mapping: GNSS aids in geospatial mapping, surveying, and precision agriculture, optimizing resource allocation and land management practices.
• Emergency Response: GNSS facilitates emergency response efforts by enabling responders to accurately locate and coordinate rescue operations.

Given their ubiquitous use, any disruption or manipulation of GNSS signals can have profound consequences, ranging from financial losses to compromised safety and security.

Emerging Cyber Threats to GNSS Systems

Despite their importance, GNSS systems are vulnerable to various cyber threats, including:

1. Spoofing Attacks: Spoofing involves broadcasting false GNSS signals to deceive receivers about their location or time. This manipulation can lead to mis navigation or synchronization errors, potentially causing accidents or disrupting critical operations.
2. One of the main GPS vulnerabilities is spoofing, which is when a malicious actor sends false GPS signals to a receiver, tricking it into thinking it is in a different location. This can lead to serious consequences, such as misleading aircraft and ships, disrupting transportation, and interfering with military operations. Prior to Russia’s invasion of the Ukraine back in 2021, two NATO warships had their positions spoofed while in port in Odessa, after they had been conducting exercises in the Black Sea with Russian military ships nearby.  
3. Jamming Attacks: Jamming attacks involve transmitting high-power radio signals to overwhelm GNSS signals, rendering receivers unable to acquire accurate positioning or timing information. Such attacks can disrupt GNSS-dependent services and infrastructure, leading to operational disruptions and service outages.
4. Another GPS vulnerability is jamming, which is when a malicious actor sends a powerful radio signal to interfere with the GPS signal, causing it to be lost or distorted. Given the relatively weak signals that come from the space-based GPS signals, a jammer can often be small in size – and simply need to use the same frequency as GPS to emit a radio signal that causes interference, overpowering the GPS signal. This can disrupt communication and navigation systems, leading to potential accidents, and chaos. Small jammers (while illegal) can be purchased online – and are frequently used by individuals who do not want to be tracked (e.g., truckers who don’t want to be tracked by their employers). On a larger scale, not only has Russia been jamming GPS in and around the Ukraine since the invasion (which has caused issues across Europe with flights using GPS), but back in October of 2022, there were noted issues of GPS interference around Dallas – causing issues at the Dallas airport and impacting travelers. 
5. Cyber Intrusions: Attacks targeting the ground infrastructure that supports GNSS operations, such as control centers and satellite uplink stations, can compromise the integrity and availability of GNSS services. Cyber intrusions may result in data breaches, system disruptions, or unauthorized access to critical assets.

Strategies for Protecting GNSS Systems

To safeguard GNSS systems from cyber threats, a comprehensive approach encompassing technological, operational, and regulatory measures is essential:

1. Enhanced Signal Authentication: Implementing robust authentication mechanisms within GNSS signals can help verify their integrity and authenticity, mitigating the risk of spoofing attacks.
2. Resilient Receiver Designs: Developing secure receiver designs with built-in defenses against known cyber vulnerabilities can enhance the resilience of GNSS systems to cyber-attacks.
3. Real-time Monitoring and Anomaly Detection: Deploying advanced monitoring and anomaly detection systems can enable early detection and mitigation of jamming and spoofing attacks, ensuring the continuity of GNSS services.
4. Redundancy and Diversity: Incorporating redundancy and diversity in the GNSS constellation and ground infrastructure can improve system resilience and mitigate the impact of cyber incidents.
5. International Cooperation and Standards: Fostering international cooperation and collaboration among GNSS stakeholders is crucial for sharing threat intelligence, best practices, and standards for securing GNSS systems against cyber threats.

Recognizing these threats, in the fall of 2022, the Department of Homeland Security’s Cybersecurity and Infrastructure Security Agency has classified PNT vulnerabilities as cybersecurity threats. These threats can often appear as “Denial of Service” or “Man in the Middle” kinds of cyber attacks. Without mitigation strategies (including having a resilient PNT system in place), these kinds of GPS attacks could impact transportation, communication, and critical infrastructure. It is important to address these vulnerabilities by implementing measures to detect and mitigate spoofing and jamming attacks, ideally providing a resilient layer to GPS with complementary PNT technology – including NextNav’s TerrapoiNT. 

Conclusion

Protecting GPS and GNSS systems from cyber threats is paramount to safeguarding critical infrastructure, ensuring public safety, and preserving economic stability. By adopting a proactive and collaborative approach that combines technological innovation, operational best practices, and regulatory frameworks, we can strengthen the resilience of GNSS systems and mitigate the risks posed by cyber adversaries. In doing so, we can continue to harness the benefits of GNSS technology for the betterment of society while minimizing the vulnerabilities inherent in our interconnected world.