This so-called vulnerability is a design choice made by WhatsApp
WhatsApp users were thrown into a panic Friday morning after a report claimed the service has a backdoor that could allow messages to be intercepted, but experts and WhatsApp say that claim is false.
A report from The Guardian said the “security backdoor” could allow WhatsApp or government snoops to intercept messages, but the security researcher who The Guardian cited called it a vulnerability, not a backdoor.
In an April blog post, Tobias Boelter explained how WhatsApp’s security structure could potentially allow someone to intercept messages by pretending to be a recipient. In fact, this so-called vulnerability is a design choice made by WhatsApp so chats can flow uninterrupted.
WhatsApp users can enable a setting on the app that will alert you when your friend changes devices after your message is delivered. Users are advised to ask friends in person or through a different channel to confirm that they changed devices if you’re worried about security.