Last month, the US Maritime Administration filed a bizarre report, in which at least 20 Russian ships appeared on trackers to be in the same spot 20 miles (32 kilometres) inland, despite being at various positions in the Black Sea.

While this initially appeared to be a glitch, experts now suggest that Russia may have been testing a new system for spoofing GPS.

If this is the case, it could be a worrying first step towards electronic warfare in which movements can't be traced.

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On June 22, the US Maritime Administration filed a bizarre report, in which at least 20 Russian ships appeared on trackers to be in the same spot 20 miles (32 kilometres) inland, despite being at various positions in the Black Sea. While this initially appeared to be a glitch, experts now suggest that Russia may have been testing a new system for spoofing GPS (stock image)

WHAT IS GPS SPOOFING? A GPS spoofing attack involves broadcasting incorrect GPS signals to trick a GPS receiver. The fake signals cause the receiver to estimate its position to be somewhere other than where it actually is, as determined by the attacker. And while early versions were technically very difficult to create, experts say that more modern versions could easily be built with commercial hardware and software easily accessible online. The amount of power needed for GPS spoofing is also not very high, and Dr Humphreys predicts that a transmitter would need just one-watt of power for spoofing. Advertisement

The report was filed by the US Maritime Administration after the master of a ship off the coast of Russia discovered that his GPS had put him in the wrong spot.

And after contacting other ships nearby, the captain discovered that the same issue had affected at least 30 other ships.

Speaking to New Scientist, experts have said that they think the incident is the first documented use of GPS misdirection.

Previous studies have suggested that the biggest threat to GPS is jamming, in which the satellite signal is masked with noise.

But while this can be an issue, it is very easy to detect – unlike spoofing.

David Last, former president of the UK's Royal Institute of Navigation told New Scientist: 'Jamming just causes the receiver to die, spoofing causes the receiver to lie.'

Other experts have been warning of such a threat for years.

In 2013, Dr Tod Humphreys, an associate professor in robotics at the University of Texas at Austin showed that a yacht could be lured off-course by GPS spoofing.

Dr Humphreys said: 'The receiver's behaviour in the Black Sea incident was much like during the controlled attacks my team conducted.'

Dr Humphreys suggests that Russia has been testing out a new form of electronic warfare.

Since 2016, phone apps, including Pokemon Go, have been mysteriously redirecting users from the Kremlin (pictured) to Vnukovo Airport, 20 miles (32 kilometres away)

HOW COULD GPS SPOOFING BE USED? As GPS spoofing systems become easier to make, Dr Humphreys highlights that any hacker could make their own version. This could allow hackers to carry out a range of dangerous tasks, including diverting driverless cars or drones, or even hijacking ships. The biggest threat, however, is GPS spoofing in the hands of a state operator, according to Dr Humphreys. He said: 'It affects safety-of-life operations over a large area. 'In congested waters with poor weather, such as the English Channel, it would likely cause great confusion, and probably collisions. 'My gut feeling is that this is a test of a system which will be used in anger at some other time.' Advertisement

Since 2016, phone apps, including Pokemon Go, have been mysteriously redirecting users from the Kremlin to Vnukovo Airport, 20 miles (32 kilometres away).

And it seems that GPS spoofing has now extended beyond the Kremlin.

While Dr Humphreys' GPS spoofing system was technically very difficult to create, he says that more modern versions could easily be built with commercial hardware and software easily accessible online.

The amount of power needed for GPS spoofing is also not very high, and Dr Humphreys predicts that a transmitter would need just one-watt of power.

And as GPS spoofing systems become easier to make, Dr Humphreys highlights that any hacker could make their own version.

This could allow hackers to carry out a range of dangerous tasks, including diverting driverless cars or drones, or even hijacking ships.

The biggest threat, however, is GPS spoofing in the hands of a state operator, according to Dr Humphreys.

He said: 'It affects safety-of-life operations over a large area. In congested waters with poor weather, such as the English Channel, it would likely cause great confusion, and probably collisions.

'My gut feeling is that this is a test of a system which will be used in anger at some other time.'