What is GNSS/GPS spoofing?
GNSS/GPS spoofing is a cyberattack technique that uses false GPS signals with the intent to deceive receivers and display incorrect location and or time data. GNSS/GPS is possible by abusing the vulnerability of GPS, which is the relative weakness of satellite signals when reach the receiver. Spoofing happens when stronger, inauthentic signals overpower weaker, authentic ones. These stronger signals with fake data are sent from a radio transmitter to a nearby target receiver. The term GNSS/GPS spoofing addresses spoofing of GPS signals in particular, but GNSS spoofing can potentially can happen with satellite signals from any GNSS.
The intent of spoofing is deceit, caused by intentionally sending out incorrect location and time data so that a GPS device displays an incorrect location on Earth. Because many day-to-day applications rely on precise location and time data, signal or position loss as a result of spoofing is costly and dangerous. Telecom networks, banks, and power grids rely on GNSS time, while industries such as surveying, logistics, and construction use precise positioning for ease for automation, efficiency, and safety.
In addition to displaying false location and time data which undermines capturing trustworthy data capture anytime, anywhere, spoofing can have negative consequences on GNSS equipment and hardware: for example, frequently recalibrating GNSS systems can be time-intensive, while constant processing of corrupted or deceitful signals may cause them to overheat, which reduces their lifespan.
GNSS signals differ significantly in power, modulation, encryption, and bandwidth, which affects how resistant they are to spoofing. Three different categories address the level of spoofing susceptibility of different L-band signals: most susceptible, moderately resistant, and most resistant to spoofing. For example, the GPS L1 C/A band belongs to the first category, being an open, civilian signal and therefore easy to imitate. GPS L2C is moderately resistant to spoofing, being harder to imitate cleanly due to multipronged signal structure. An example of most resistant to spoofing is GPS L1 P(Y), an encrypted military signal, where spoofing would require breaking encryption or coercing receivers via power overshadowing. Thise is a non-authentic way of forcing a GNSS receiver to ignore the real signal by transmitting a stronger signal on the same frequency.
GNSS receivers offer multiple levels of spoofing prevention. These include signal monitoring and anomaly detection, multi-system cross-verification, cryptographic authentication, and crowd-sourced data analysis. New advanced techniques strengthen GPS systems beyond spoofing detection. These include GPS firewalls, Inertial Navigation Systems (INS) integration, multi-antenna systems and beamforming, and MEMS-based oscillators for timing stability.
Advanced Navigation for example has introduced a new line of defense-ready inertial navigation systems (INS), featuring integrated Electronic Protection (EP) capabilities to counter global GNSS jamming and spoofing engagements. The EP range enable seamless integration into new-build and legacy platforms, including combat vehicles, UGVs, artillery, C-UAS, radar pointing systems, ISR payloads, UAVs, USVs and autonomous underwater systems.
Although high-end GNSS receivers that employ spoofing detection and mitigation methods are still relatively safe from spoofing efforts, there is no reason for complacency. This explains why GNSS receiver manufacturers develop new technology to address the issue. The following provides a brief overview of recent anti-spoofing technology from the industry:
Trimble
Introduced earlier this year, Trimble RTX-NMA (Navigation Message Authentication) the first solution on the market to mitigate spoofing attacks on the GPS and BeiDou satellite constellations. Trimble RTX-NMA seeks to detect both fake GNSS signals and faulty ephemeris data through real-time authentication that ensures navigation messages from multiple RTX reference station receivers are genuine and trustworthy.
The mosaic-G5 T is Septentrio’s latest receiver, offering nano-second time precision complemented by AIM+ Premium anti-jamming and anti-spoofing2 technology, ensuring reliable service uptime and continuity. The built-in cyber-security features make the timing receiver ideal for critical infrastructure that requires a resilient, high-quality timing source such as data centers, telecom, satcom, financial institutions and more.
As GNSS/GPS signals continue to underpin critical infrastructure, automation, and everyday applications, the threat of spoofing grows more consequential. What was once a niche cybersecurity concern has become a mainstream operational risk, capable of disrupting industries that depend on precise positioning and timing. While no single method can eliminate spoofing entirely, recent advances—from multi-layer detection techniques to emerging authenticated navigation messages and EP-enabled INS systems—mark a significant step toward stronger resilience. Manufacturers are pioneering solutions to help ensure GNSS-reliant systems remain trustworthy even in contested environments. Ultimately, staying ahead of spoofing requires constant innovation, layered defenses, and an industry-wide commitment to safeguarding the signals that keep modern society synchronized and moving.
