Ships around the world are reporting false locations, seeming to circle Point Reyes near San Francisco when they are actually thousands of kilometres away.
The locations are broadcast by each ship鈥檚 Automatic Identification System (AIS). These are required under international law to signal a vessel鈥檚 identity and GPS location. Bjorn Bergman of the environmental watchdogs SkyTruth and Global Fishing Watch discovered the anomalies from a historical database of AIS information.
Bergman was tipped off when he noticed records from 2018 and 2019 of satellites receiving AIS locations outside areas they cover, for example, a satellite over West Africa picking up a ship supposedly off California. Vessels affected included a livestock carrier near Libya, a cargo ship in the Suez Canal, a small boat off Chile and a Norwegian tug.
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Most incidents lasted just a few hours, but a boat carrying oil workers to installations off the coast of Nigeria spent two weeks apparently circling Point Reyes, then veered off inland to Utah, occasionally jumping back to a Nigerian oil terminal.聽Most vessels appeared to circle off California, but others were displaced to Madrid or Hong Kong.
The exact source and motive for the spoofing remains a mystery. There is no obvious reason to pick Point Reyes for the false reports, although that location was significant in the history of navigation as the site of one of the first ship-to-shore radio facilities.
One theory is that the spoofing may be an attempt to protect oil platforms from drones 鈥� Saudi oil facilities were 鈥� but that wouldn鈥檛 explain all of the incidents. 聽鈥淲e have a number of ideas, but nobody knows exactly what is going on,鈥� says Bergman.
GPS can be fooled by spoofing, where a transmitter imitating a GPS satellite sends false data. In 2017, 20 ships in the Black Sea reported a position 32 kilometres inland at Gelendzhik Airport in Russia, which could indicate Russian military spoofing was at work. Last year Bergman identified locations off the Chinese coast where GPS devices, including fitness trackers, gave false locations showing them elsewhere going in small circles.
Dana Goward at the Resilient Navigation and Timing Foundation in the US says that the latest cases are different because they don鈥檛 affect all vessels in an area.
鈥淚t is pretty clear that the previous incidents were sponsored by governments or large government-backed organizations,鈥� says Goward, because they could only have been carried out using large, military-type hardware. 鈥淚n these new cases, only one vessel was impacted so the device was likely low power, and short range.鈥�
Goward says this indicates small devices, possibly on board the affected vessels. 鈥淚 suspect that government spoofing equipment has recently transitioned to the consumer market and that is why we are seeing these events,鈥� he says.
Read more: GPS chaos: How a $30 box can jam your life
Todd Humphreys at the University of Texas at Austin has long been warning of the danger of GPS spoofing and in 2013 . He agrees that the latest incidents show an evolution of technology.
鈥淥ver a decade ago, Chinese companies began to offer cheap [GPS] jammers, which became known as 鈥榩ersonal privacy devices鈥�,鈥� says Humphreys. 鈥淚 think what we鈥檙e witnessing here is the emergence of commoditised spoofing:聽 someone has begun selling a low-cost spoofing device for use on ships.鈥�
Such devices are a real escalation. While a jammer simply causes GPS devices to fail, a spoofer gives a false position, and could allow a fishing vessel to stealthily enter prohibited waters or falsify the route taken by smugglers. This previously required sophisticated technical know-how, says Humphreys.
There haven鈥檛 been any known accidents due to the spoofing, but ships rely on AIS to avoid collisions, so there is the potential for major disaster.
