Interessanter Bericht bzgl. der Sicherheit von Gruppenchats in Signal, WhatsApp und Threema:
https://web-in-security.blogspot.de/2017/07/insecu…ignals-and.html
https://eprint.iacr.org/2017/713.pdf
Interessant sind vor allem die Reaktionen:
"As described earlier, Threema updated their application in response to our responsible disclosure. Consequently No Duplication, No Creation, and Closeness are not attackable anymore." (Die Korrektur ist in Version 3.14 bereits drin).
"Moxie Marlinspike responded that Signal is working on an entirely new group mechanism that we should be deploying soon"
"WhatsApp did not hold out the prospect of fixing the described vulnerabilities."