The Syrian Electronic Army sent out a warning over Twitter earlier Tuesday that said, "If you have 'Viber' app installed we advise you to delete it."
The hacking group was claiming responsibility for both breaching Viber's database and defacing its Web site, according to The Hacker News.
Right after the breach, Viber's support page on its Web site displayed a banner that said "Hacked by Syrian Electronic Army" and a note that said "Dear All Viber Users, the Israeli-based 'Viber' is spying and tracking you." As of this writing, the banner is no longer up and instead a "403 Forbidden" message is displayed.
Viber is an app that lets users call and message via Wi-Fi for free. In May, it announced that it had more than 200 million users spread across 193 countries.
The company confirmed to TechCrunch that indeed its Web site was defaced but that sensitive user information was not stolen.
Not a Viber user myself but to those that are it's big news. Apparently no personal information was accessed or stolen so looks like a plain web site hack.