WhatsApp has introduced a new security feature that fixes a loophole that could allow an attacker to hijack victim’s account with just knowing the victim’s phone number and some hacking skills. The attack does not exploit any vulnerability in WhatsApp; instead, it relies on the way the account setup mechanism works. For now, the feature is available only on WhatsApp beta version, and the company will start rolling out two-step verification with the release of a stable version for both iOS and Android for over 1 Billion users in the coming weeks.
Source: https://thehackernews.com/2016/11/whatsapp-two-step-verification.html