Researchers discover security vulnerability in WhatsApp

Researchers from the University of Vienna and SBA Research discovered a significant privacy vulnerability in WhatsApp's contact discovery mechanism, allowing the enumeration of 3.5 billion accounts. The vulnerability enabled the querying of over 100 million phone numbers per hour, exposing public data such as phone numbers, public keys, and profile information. Meta, WhatsApp's operator, has addressed the issue and implemented countermeasures. The study highlights the importance of continuous security research and the risks associated with centralized messaging services.