A new study reveals that sensitive, unencrypted data from military, corporate, and telecommunication sources is being transmitted openly via geostationary satellites. Researchers from two U.S. universities successfully intercepted this information using commercially available equipment that cost only $600, challenging the long-held belief that such surveillance requires significant government resources.
The findings highlight a major security gap in how organizations protect data transmitted over satellite networks. The seven-month study demonstrated the ease with which private communications, including phone calls, text messages, and internal corporate data, can be captured by anyone with basic equipment and a clear view of the sky.
Key Takeaways
- Researchers intercepted unencrypted data from 39 satellites using $600 worth of consumer-grade equipment.
- Sensitive information from the U.S. military, telecommunications firms like T-Mobile and AT&T, and the Mexican government was exposed.
- The study found that many organizations fail to use standard network-layer encryption, such as IPSec, over satellite links.
- Data collected included plaintext SMS messages, voice call content, user browsing history, and internal corporate network traffic.
- The research proves that satellite eavesdropping is accessible to individuals, not just well-funded intelligence agencies.
A Low-Cost Method for High-Stakes Eavesdropping
A joint research team from the University of Maryland and the University of California, San Diego, set out to determine the accessibility of satellite data interception. Their goal was to see if a low-budget setup could passively collect sensitive information from geostationary (GEO) satellites, which are crucial for global communications.
Over a period of seven months, the team scanned 39 different satellites across 25 distinct orbital positions. Using simple, off-the-shelf equipment, they successfully captured a wide range of unencrypted data transmissions.
The study, authored by Wenyi Zhang, Annie Dai, Keegan Ryan, Dave Levin, Nadia Heninger, and Aaron Schulman, provides compelling evidence that the barrier to entry for satellite surveillance is much lower than previously assumed. Their work suggests that technical knowledge, rather than a large budget, is the primary requirement.
"Given that any individual with a clear view of the sky and $600 can set up their own GEO interception station from Earth, one would expect that GEO satellite links carrying sensitive commercial and government network traffic would use standardized link and/or network layer encryption to prevent eavesdroppers," the researchers wrote.
Widespread Data Exposure Across Multiple Sectors
The information intercepted by the researchers was both varied and highly sensitive. The team observed unprotected data streams from major telecommunications providers, government bodies, and military operations. This demonstrates a systemic failure to secure satellite communication channels.
What Are Geostationary Satellites?
Geostationary satellites orbit the Earth above the equator at an altitude of approximately 35,786 kilometers (22,236 miles). At this height, their orbital period matches the Earth's rotation, causing them to appear stationary from the ground. This fixed position makes them ideal for providing continuous communication services, including television broadcasting, internet access, in-flight Wi-Fi, and private network backhaul for remote locations.
Telecommunications and Civilian Data
The study identified significant data leaks from several telecommunication companies. For T-Mobile customers, the researchers captured a large volume of personal information. This included:
- Plaintext SMS messages
- Contents of voice calls
- Complete user internet traffic and browsing history
- Call metadata, including phone numbers
In a single nine-hour listening session focused on one satellite beam, the team collected phone numbers and metadata associated with 2,711 different individuals. Similar vulnerabilities were found in the networks of Mexican telecoms TelMex and WiBo, as well as the Alaskan provider KPU Telecommunications.
Military and Government Communications
The surveillance also extended to government and military traffic. The researchers intercepted unencrypted communications from U.S. military sea vessels. The plaintext data was detailed enough to include the ships' names, which allowed the team to identify them as government-owned vessels that were formerly in private hands.
Furthermore, the team gained insight into internal military systems by capturing unencrypted HTTP traffic. This exposed details about applications used for infrastructure management, logistics, and administrative tasks. Communications from the Mexican government were also observed during the study.
Focus on Ku-Band Transponders
The research specifically targeted Ku-Band transponders on the satellites. This band of frequencies is widely used for internet services, television broadcasting, and data backhaul for private networks. The team successfully monitored 411 different transponders, indicating the broad scope of the potential vulnerability.
A Misplaced Trust in Satellite Security
The core issue identified by the researchers is that many organizations treat satellite links as if they are secure, private wires within their internal network. This assumption leads them to neglect fundamental security practices, such as implementing network-layer encryption.
"Many organizations appear to treat satellite[s] as any other internal link in their private networks," the paper states. "Our study provides concrete evidence that network-layer encryption protocols like IPSec are far from standard on internal networks."
This oversight is particularly dangerous because satellite signals are broadcast over vast areas, making them inherently susceptible to interception. The researchers noted that the severity of their findings suggests that many organizations do not actively monitor the security of their own satellite links.
Between December 2024 and July 2025, the academic team responsibly disclosed their findings to the affected parties. These included the U.S. military, T-Mobile, AT&T, Panasonic Avionics, and IntelSat, among others. The researchers stated they declined any bug bounty offers that required a non-disclosure agreement to ensure the information could be made public.
Implications for National and Critical Infrastructure
The study's findings raise serious questions about the security of vital communication systems. Satellites provide essential connectivity for remote and rural areas, serve as backhaul for cellular networks, and support critical operations for both commercial and government entities.
Despite their importance, space-based systems are not currently one of the 16 sectors officially designated as "critical infrastructure" by the U.S. federal government. This designation typically brings increased security investment and regulatory attention. Policymakers have previously argued for the inclusion of space systems to address growing security concerns.
This research underscores the urgency of that conversation. By proving that significant surveillance can be conducted with minimal investment, the study highlights a vulnerability that could be exploited by a wide range of actors, from individual hobbyists to malicious groups, far beyond the scope of state-level intelligence agencies. The report concludes that a fundamental shift in how satellite communications are secured is necessary to protect private and sensitive data.