“Please do not make it public”: Vulnerabilities in Sogou Keyboard encryption expose keypresses to network eavesdropping::In this report, we analyze the Windows, Android, and iOS versions of Tencent’s Sogou Input Method, the most popular Chinese-language input method in China. Our analysis found serious vulnerabilities in the app’s custom encryption system and how it encrypts sensitive data. These vulnerabilities could allow a network eavesdropper to decrypt sensitive communications sent by the app, including revealing all keystrokes being typed by the user. Following our disclosure of these vulnerabilities, Sogou released updated versions of the app that identified all of the issues we disclosed.
These vulnerabilities could allow a network eavesdropper to decrypt sensitive communications sent by the app, including revealing all keystrokes being typed by the user.
Why are these keystrokes being sent over the network to begin with?
For longer strings of syllables, an IME will commonly reach out over the network to a cloud-based service for suggestions if suitable suggestions are not available in the input method’s local database.
This seems particularly dangerous that it’s for Chinese users.