A padlock over streams of binary code, illustrating verified cryptographic security
Image: A padlock over streams of binary code, illustrating
verified cryptographic security. Image credit: Stock photo.

 

Google DeepMind has mathematically verified the encryption behind Signal, WhatsApp and Google Messages, and it took an AI system four weeks to do it.

Researchers at Google DeepMind used agentic AI to formally verify several of the Signal protocol's key cryptographic guarantees, completing the work as a proof-of-concept project in about four weeks, WIRED reported on November 10, 2026. The analysis used a new AI framework called AlphaProof Code. It found no new vulnerabilities in the portions of the protocol it examined, and it independently confirmed that the encryption protecting some of the world's most-used messaging apps works as designed.

What does formal verification actually mean?

Formal verification is the practice of proving with mathematics that software behaves exactly as intended, rather than testing it and hoping the tests catch every bug. Security researchers have long called it a holy grail, because a proof rules out entire classes of vulnerabilities, including the ones nobody has thought to look for. Before AI, the work was slow and expensive: describing what to prove, turning that into formulas and writing the proof itself could take months. Agentic AI compresses much of that proof-writing work, which is what made a four-week Signal analysis possible.

How did AlphaProof Code check Signal's encryption?

The team built on earlier formal verification work from the Signal Foundation, which had covered smaller portions of the code. DeepMind's approach expanded the coverage significantly. Crucially, when the researchers pointed AlphaProof Code at older versions of Signal that contain known and long-fixed vulnerabilities, the tool correctly flagged them and demonstrated that those versions could not be formally verified as secure, which is a strong sign the method is actually checking rather than rubber-stamping. DeepMind is releasing the specification and proof publicly so other teams can build on it.

What are the limits of this result?

The analysis did not cover the entire Signal mobile app, and DeepMind has not disclosed what the project cost or whether a commercial verification product will follow. "We are very excited by this result, but there is a long distance to go before we are able to scale this to all the software of the world, and we want to do that," Swarat Chaudhuri, a DeepMind research scientist, told WIRED. Signal's chief technology officer, Ehren Kret, said the work "enables significant expansion" over prior verification efforts and gives "even greater confidence in our code's privacy guarantees."

Why should Nigerian users and businesses care?

The Signal protocol is the foundation of WhatsApp's encryption, an app used by tens of millions of Nigerians daily for family chats, business deals and even official government communication. Independent, math-level validation of that protocol is meaningful reassurance that messages stay private. Pushmeet Kohli, DeepMind's vice president of research, framed the broader stakes: "You can imagine banks, imagine all those other companies who rely on assurances and who worry about bugs who could now say, 'I can prove these properties.'" For companies running any security-critical software, AI-assisted proof is worth watching as the tools mature.

Frequently asked questions

Did the AI find any vulnerabilities in Signal?
No. It found no new vulnerabilities in the portions it examined, and it correctly identified known vulnerabilities in older versions that were fixed long ago.

Does this mean WhatsApp is now more secure?
Not directly. The work validates the Signal protocol's core guarantees, which strengthens confidence in the encryption WhatsApp, Signal and Google Messages already use.

What is AlphaProof Code?
A new Google DeepMind framework that uses agentic AI to write and check mathematical proofs about software behaviour.

Sources: WIRED, "A New AI Tool From Google DeepMind Proved the Signal Protocol Is Secure" by Lily Hay Newman (wired.com, November 10, 2026); statements from Google DeepMind researchers and Signal CTO Ehren Kret via WIRED. Related reading on this blog: OpenAI's Control Room safety switch and xAI's default-on watermark for API text.