How does WhatsApp implement encrypted group chats? And are they secure? @malb.bsky.social, @bedow.bsky.social and myself were keen to figure this out. After two years of reverse-engineering, analysis and a few too many proofs, I presented our work at Eurocrypt earlier today. So, what did we learn?

Excited to announce a funded PhD position analysing the Social Foundations of Cryptography here at King's College London with me and @malb.bsky.social . Applications open now, feel free to reach out for a chat. social-foundations-of-cryptography.gitlab.io Link in next post!