The defacement page states, "Dear All Viber Users, The Israeli-based 'Viber' is spying and tracking you. We weren't able to hack all Viber systems, but most of it is designed for spying and tracking."
On their own Web site, the hackers added, "The SEA downloaded some of the app databases, and after we gain access to some systems of that app, it was clear for us that the [purpose] of this app is spying and tracking of its users."
According to E Hacking News, the hackers also published the names, e-mail addresses and phone numbers of 11 Viber administrators, along with a screenshot showing several phone numbers, UDIDs, countries, IP addresses, registration dates and other data.https://o1.qnsr.com/log/p.gif?;n=203;c=204650394;s=9477;x=7936;f=201801171506010;u=j;z=TIMESTAMP;a=20392931;e=i
In a statement provided to Cult of Mac, Viber said the breach was the result of a phishing attack, which provided the hackers with access to a customer support panel and a support administration system. "It is very important to emphasize that no sensitive user data was exposed and that Viber’s databases were not 'hacked,'" the company stated. "Sensitive, private user information is kept in a secure system that cannot be accessed through this type of attack and is not part of our support system."