On Wednesday, November 11, 2026, Google DeepMind's AI formally verified key parts of the Signal protocol in just four weeks.
The four-week proof-of-concept used an AI framework called AlphaProof Code to check cryptographic guarantees tied to Signal, Google Messages and WhatsApp. It found no new vulnerabilities in the parts reviewed, while testing older Signal versions with known flaws and showing those versions could not be formally verified. The result marks a milestone, not a full verification of the entire Signal app, and scaling AI-aided formal verification remains a challenge.