An Israeli advertising technology company has come under scrutiny after cybersecurity researchers linked its activities to the tracking of Starlink satellite internet users across more than 100 countries.

According to Reuters, researchers at TrendAI identified Discover-Tech as a major bidder for digital advertisements displayed to Starlink users, including in countries where the satellite internet service is banned or restricted.

The investigation found that the company’s advertising activity could have been used to collect technical information and identify the locations of Starlink users through digital advertising systems.

Researchers from TrendAI, Citizen Lab and advertising security firm Confiant examined how information generated during online advertising auctions could expose details about internet users and their browsing activity.

The findings raised particular concerns about surveillance in conflict zones and countries with restrictions on Starlink, including Syria, Libya, Yemen and Afghanistan.

A separate Citizen Lab investigation also linked infrastructure associated with Discover-Tech to surveillance techniques that could potentially deliver spyware without requiring users to click on malicious links.

Following the disclosures, Google and Comcast removed Discover-Tech from their advertising networks. The investigations have renewed concerns about the privacy risks associated with online advertising systems.