Viber takes the safety of user data seriously. All text messages sent through Viber on all the platforms supporting it are encrypted. Media data, such as photo or video files, is encrypted. Encryption is present on iOS, Android, Windows 8 and Windows Phone 8. Everything you send or write to someone else will be encrypted and accessible to anyone who might try to get their hands on your private correspondence.
As you can read in "Viber communication security": For Viber we can conclude it uses some kind of encryption but what kind of encryption is unclear.
Have you used Viber before? For those of you who do not know it, ... Viber Has No Encryption Protection By Edwin Kee on 04/24/2014. Have you used Viber before?
Apr 24, 2014 · Viber does not utilize encryption when sending, receiving or storing location data and communications, making the information easy to compromise.
Jul 30, 2014 · While in the IDF, he boned up on encryption, which forms the backbone of Viber. Viber currently has research and development facilities in Israel and Belarus.