Massive leak exposes China's Great Firewall censorship technology
Over 500GB of source code, logs and internal communications from China's Great Firewall were leaked in September 2025, revealing that the Geedge Networks company and related institutions built surveillance tools for China's censorship system and exported similar technologies to at least five countries including Kazakhstan, Ethiopia, Myanmar and Pakistan.
What happened
On September 11, 2025, over 500GB of source code, work logs and internal communications from China's Great Firewall were leaked, revealing technical details of the censorship and surveillance system.
The leaked files originated from Geedge Networks Ltd. (積至公司) and the Chinese Academy of Sciences Information Engineering Research Institute's MESA laboratory, and showed that these institutions built and exported network monitoring tools to at least five countries: Kazakhstan, Ethiopia, Myanmar, Pakistan, and one country identified only as 'A24'.
Geedge Networks was founded in 2018 by Fang Binxing, known as the 'father of the Great Firewall,' who serves as chief scientist. The company's core technical team came from the MESA laboratory.
Reported impact
The leaked files revealed that Geedge Networks' flagship product, the Tiangou Secure Gateway (TSG), provides website and application filtering, real-time network monitoring, regional traffic restrictions, user identification through network traces, and blocking of virtual private networks and other circumvention tools.
TSG Galaxy stores metadata on TCP and UDP sessions and allows monitoring of internet traffic as well as telephone calls. Cyber Narrator tracks individual network traffic in real time and can identify users of circumvention tools and geolocate mobile users by associating activity with specific neighborhood identifiers.
Index analysis
The leaked files showed that Geedge Networks deployed TSG to Kazakhstan starting in 2019 and to Ethiopia beginning in 2021 in cooperation with the local telecommunications operator Safaricom, with deployment timeline correlating to Ethiopia's social media blocking in February 2023.
Geedge Networks works with provincial governments in Xinjiang, Jiangsu and Fujian to build provincial-level firewalls separate from the national Great Firewall, and the company operates under China's 'Belt and Road Initiative' framework, particularly its 'Digital Silk Road' component.
Classification
Sources and evidence
This record was researched and written by the Index, based on the following original reporting.