Within mainland China, we found that Apple censors political content including broad references to Chinese leadership and China’s political system, names of dissidents and independent news organizations, and general terms relating to religions, democracy, and human rights. And across all six regions, we found that Apple’s content moderation practices pertaining to derogatory, racist, or sexual content are inconsistently applied and that Apple’s public-facing documents failed to explain how it derives their keyword lists.

As a follow-up to our March 2020 report, we conducted daily tests on WeChat and collected 2,174 censored keywords between January to May 2020. This data provides a view into how narratives and messaging on the pandemic are controlled and molded on social media in China.

On May 7 2020, the Citizen Lab published a report that documents how WeChat (the most popular social app in China) conducts surveillance of images and files shared on the platform and uses the monitored content to train censorship algorithms. This document provides a summary of the research findings and questions and answers from the research team.

WeChat communications conducted entirely among non-China-registered accounts are subject to pervasive content surveillance that was previously thought to be exclusively reserved for China-registered accounts.

The analysis of YY and WeChat indicates broad censorship—blocking sensitive terms as well as general information and neutral references—potentially limiting the public’s ability to access information that may be essential to their health and safety.

This campaign is the first documented case of one-click mobile exploits used to target Tibetan groups, and reflects an escalation in the sophistication of digital espionage threats targeting the community.

In this work, we study how Tencent implements image filtering on WeChat. We found that Tencent implements realtime, automatic censorship of chat images on WeChat based on what text is in an image and based on an image’s visual similarity to those on a blacklist. Tencent facilitates this realtime filtering by maintaining a hash index of MD5 hashes of sensitive image files.

New Citizen Lab research reveals how China’s most popular app filters sensitive images and suggests techniques for evasion.

This report demonstrates the technical underpinnings of how WeChat image censorship operates and suggests possible evasion strategies.