WeChat Monitors Files Shared by International Users to Bolster Censorship in China, Says Citizen Lab
WeChat has over 116.4 crore users worldwide.
By┬аJagmeet Singh
WeChat, a popular messaging app with more than 100 crore users on board worldwide, is monitoring documents and images shared by users registered outside China, to censor these materials from its Chinese users. The app, backed by Internet giant Tencent, silently subjects its international users to surveillance, analysing files shared by them using a remote server, according to a study by Citizen Lab, the research group that earlier revealed the Pegasus attack on WhatsApp.
The surveillance is allegedly used to bolster censorship that┬аWeChat┬аalready has for its registered users in China. However, the app doesn't censor content for non-China registered accounts, only monitors them.
Researchers of the University of Toronto's security research group Citizen Lab have┬аdetermined┬аthat WeChat screens documents and images people share through the platform when using phone number not registered in China. The app uses this remote server that conducts the surveillance process, without giving any signs to end-users, according to Citizen Lab. If the server recognises the content as тАЬpolitically sensitiveтАЭ, it adds a digital signature in the form of an MD5 hash, to flag that file so that it can be kept away from China-registered users.
In the study, titled тАЬWe Chat, They WatchтАЭ, the Citizen Lab's researchers noted that multiple tests were conducted between November 2019 and January 2020 to analyse the surveillance behaviour of WeChat. The content screening nature that emerged through the tests wasn't clearly explained in any of the app's privacy agreements and policy documents, the researchers said.
Neither WeChat nor its parent company┬аTencent, which is also an investor in┬аFlipkart,┬аPracto,┬аSwiggy, and more, have responded to the email sent with reference to the claims made in the study at the time of filing this story.
Real-time censorship using automated surveillance
The study included one instance in which the researchers sent a cartoon of Nobel laureate Liu Xiaobo тАФ an image deemed sensitive in China тАФ from an international account into a chat group with other users also not registered in China.
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After that, the researchers sent a second, non-sensitive image using the same MD5 hash of Xiaobo's image into a chat group that included China-registered users. The new image wasn't received by the group members тАФ despite being non-sensitive content. That exemplifies the surveillance system that is purportedly used by the app to censor content for Chinese users.
WeChat's hash index check processes the results in real-time to censor content on the platform without any delay. The automated performance of hash indexing also eases the process of surveillance on non-China registered accounts.
Infamous for censoring content
It is unclear whether the move by WeChat to screen content from non-China registered accounts is politically motivated. A report by The Wall Street Journal dated March 6┬аhighlighted┬аthat various social media platforms in China face punishments if any content that is found objectionable by the government overrides their filters.
Earlier this year, Citizen Lab┬аdiscovered┬аthat WeChat blacklisted over 500 keyword combinations related to the coronavirus outbreak, including a text referring to the Wuhan whistleblower Dr. Li Wenliang. The app was also┬аfound┬аto censor text for its China-registered users in a report by the research group in July last year.
As per the┬аofficial data┬аincluded in the recent quarterly results, WeChat has over 116.4 crore users worldwide. The app has a strong presence in China, thanks to the super-app design that means it's used for everything, from communication services such as payments, shopping, cab-hailing, video conferences, and gaming among others. It initially had good traction in India as well, though WeChat's┬аmomentum was lost┬аovertime, as Facebook-owned WhatsApp became the leading messaging app in the country.