Messages purporting to be WhatsApp invitations to try out a new voice calling feature are actually nothing more than malware conduits.
WhatsApp, one of the biggest third-party instant messaging app in the world, had 700 million active users sending 30 billion messages per day, as of January 2015, making it a popular target for scammers and hackers. To boot, it has started to roll out the hotly anticipated Free Voice Calling feature—which will add a VoIP capability to make calls, a la Skype and Viber. It’s available for Android, but it’s only invite-only for now.
Enter the cyber-scammers. Messages are going out to the WhatsApp base, inviting users to test out the new service. According to Hacker News, the invitation message appears to be from a legitimate friend, and says, "Hey, I’m inviting you to try WhatsApp Free Voice Calling feature, click here to activate now.”