- Attackers worldwide are increasingly jamming and spoofing GPS signals, endangering aircraft navigation and potentially sending planes into hostile airspace
- GPS disruption is expanding from war zones to civilian areas, affecting flights over Europe and posing a risk to aviation and telecom networks globally
- The aviation industry remains unprepared, with low-Earth orbit satellites particularly vulnerable
Attackers in conflicts worldwide are jamming and spoofing GPS signals, making it more difficult for aircraft to navigate and putting them at risk of entering into hostile airspace.
Attackers saturate GPS receivers in satellites, planes and other devices to make them unusable, Todd Humphreys, professor of engineering in the aerospace department at the University of Texas in Austin said in a keynote at the recent Brooklyn 6G Summit. These attacks have increased in recent years and will continue into the 6G era.
This electronic warfare has recently spilled over from war regions into the civilian sector, Humphreys said. Jamming has spread through Ukraine since the February 2022 start of the Russian invasion and into areas of Western Europe. Civilian flights are no longer crossing Ukraine. Jamming is “even stronger in Eastern Mediterranean and around Turkey,” the professor said.
“This has become a real problem for global aviation,” he said. “It’s going to become a problem for telecommunications networks across the globe.”
A commercial aircraft was spoofed in September 2023, “and the pilot had to call air traffic control for turn-by-turn direction vectors to his destination,” Humphreys stated. “The aircraft in question almost entered Iranian airspace without authorization.”
Security teams have seen jamming signals arising from Iran and Israel.
The aviation industry was “woefully unprepared” for GPS jamming despite 20 years of warnings, Humphreys said.
Low-Earth Orbit (LEO) satellites, which are becoming ever-more important for broadband and direct-to-cell (D2C) communications, are particularly vulnerable, he said.
We have already seen holes in the GPS map above Ukraine where LEO satellites couldn’t get a GPS fix, Humphreys said. That’s not a problem so far, as the LEO swarm has stable enough clocks and orbits that they were able to propagate through that outage. But that might not always be adequate protection. “Imagine if there were dozens of holes across the globe. Now the constellation has a hard time doing station maintenance and coordination,” Humphreys said.
3GPP Release 18 still relies on GPS for its non-terrestrial networks (NTN) space standard, Humphreys said. “I think this is unwise,” he said.
The International Telecommunication Union (ITU) put forward a resolution at the ITU World Radiocommunication Conference in 2023 designed to keep the GPS and GNSS bands clear. But there’s a loophole: “It basically says that if your country believes — for the defense of country — that it is necessary to interfere with GPS signals, then you are allowed to do so,” he said.
That’s one big loophole!
“So I say get ready because this means the floodgates are open and our networks need to be resilient to purposeful interference that may originate from a country believing that it needs to interfere in this way,” Humphreys stated.