Satellites beam data down to the Earth all around us, all the time. So you might expect that those space-based radio communications would be encrypted to prevent any snoop with a satellite dish from accessing the torrent of secret information constantly raining from the sky. You would, to a surprising and troubling degree, be wrong.
Roughly half of geostationary satellite signals, many carrying sensitive consumer, corporate, and government communications, have been left entirely vulnerable to eavesdropping, a team of researchers at UC San Diego and the University of Maryland revealed today in a study that will likely resonate across the cybersecurity industry, telecom firms, and inside military and intelligence agencies worldwide.
For three years, the UCSD and UMD researchers developed and used an off-the-shelf, $800 satellite receiver system on the roof of a university building in the La Jolla seaside neighborhood of San Diego to pick up the communications of geosynchronous satellites in the small band of space visible from their Southern California vantage point. By simply pointing their dish at different satellites and spending months interpreting the obscure—but unprotected—signals they received from them, the researchers assembled an alarming collection of private data: They obtained samples of the contents of Americans’ calls and text messages on T-Mobile’s cellular network, data from airline passengers’ in-flight Wi-Fi browsing, communications to and from critical infrastructure such as electric utilities and offshore oil and gas platforms, and even US and Mexican military and law enforcement communications that revealed the locations of personnel, equipment, and facilities.
“It just completely shocked us. There are some really critical pieces of our infrastructure relying on this satellite ecosystem, and our suspicion was that it would all be encrypted,” says Aaron Schulman, a UCSD professor who co-led the research. “And just time and time again, every time we found something new, it wasn't.”
The group’s paper, which they’re presenting this week at an Association for Computing Machinery conference in Taiwan, is titled “Don’t Look Up”—a reference to the 2021 film of that title but also a phrase the researchers say describes the apparent cybersecurity strategy of the global satellite communications system. “They assumed that no one was ever going to check and scan all these satellites and see what was out there. That was their method of security,” Schulman says. “They just really didn't think anyone would look up.”
The researchers say that they’ve spent nearly the past year warning companies and agencies whose sensitive data they found exposed in satellite communications. Most of them, including T-Mobile, moved quickly to encrypt those communications and protect the data. Others, including some owners of vulnerable US critical infrastructure whom the researchers alerted more recently—and declined to name to WIRED—have yet to add encryption to their satellite-based systems. Researchers have pointed to the surveillance dangers of unencrypted satellite connections before, but the scale and scope of the new disclosures appear unrivaled.