TextSecure, an Open WhisperSystems, is completely open-source and claims to support end-to-end encryption of text messages. Researchers from Ruhr University Bochum found that the most popular mobile messaging app is open to an Unknown Key-Share attack. The research team explained a complete and precise document and analyze of TextSecure’s secure push messaging protocol. TextSecure works on a complex cryptographic protocol which is the part of the. popular open source aftermarket Android firmware that has been installed on about 10 million Android devices.
Source: https://thehackernews.com/2014/11/textsecure-private-messenger-vulnerable_2.html