New Delhi: A major security vulnerability in WhatsApp reportedly exposed the personal details of nearly 3.5 billion users, according to research by the University of Vienna.

The researchers identified a weakness in WhatsApp’s contact discovery feature that allowed them to systematically check phone numbers and confirm active accounts on a massive scale. They generated over 100 million queries per hour using an automated method, ultimately gathering information from users in 245 countries.

Although the data accessed was limited to information already publicly visible to anyone with a phone number, such as profile photos, public keys, "about" text, and timestamps, the researchers noted that these fragments could reveal additional insights, including a user’s operating system, account age,

See Full Page