Vitalik Buterin fears AI could race through 50 years of math in five and break the cryptography securing Ethereum and Bitcoin. The Ethereum co-founder posted the concern on X the day he opened Devcon 8 in a smiley mask.

Quantum computers have long been the threat the industry plans for. However, his worry also covers lattice-based methods, the math behind several leading post-quantum standards. ETH and BTC holders could therefore face a risk that the planned quantum fixes may not fully remove.

What Could Break Crypto Before Quantum Does

Responding to a user who guessed at his reasoning, Buterin pointed to algorithms that may exist but remain undiscovered. His main example was the elliptic curve discrete logarithm problem (ECDLP), the math that protects private keys on both networks.

The co-founder also named pairings, a technique behind the signatures Ethereum validators use to vote on blocks.

I would describe my worry as: what if the equivalent of quadratic sieve for ECDLP or pairings (and similarly, more-powerful-than-today algorithms for breaking lattices) exist, and we've just not yet managed to find them – but AI speedrunning 50+ years of math in 5 years will.

— vitalik.eth (@VitalikButerin) November 3, 2026

His benchmark is the quadratic sieve, an early 1980s algorithm that sped up factoring large numbers and weakened RSA-style encryption. No such shortcut is known for ECDLP today. Instead, Buterin fears one exists and AI will find it first.

Beyond Devcon, the warning extends his recent focus on AI security. Last month, he unveiled his AI paranoid mode for private chats and backed an AI model that deliberately cut hacking skills.

The timing also put the issue in front of Devcon 8, Ethereum’s flagship developer conference in Mumbai.

A Devcon 8 Keynote Built Around Trust

On stage, Buterin paired the yellow mask with a cloak covered in eyes. It was one of his strangest looks since a dinosaur costume in 2022.

One user on X likened it to the Shoggoth meme, an AI image of a monster hiding behind a friendly mask. The monster stands for raw AI models, while the mask represents the training that makes chatbots look harmless. Buterin has not commented on his Devcon outfit.

Uh @VitalikButerin are you ressed as a Shoggoth? pic.twitter.com/ktt3MboIvj

— Shadow🌐 (@Shadowonchainn) November 3, 2026

@VitalikButerin just opened Devcon and set the tone for the week.A formally verified OS, open silicon, self-sovereign healthtech, free discourse, private communication, trustworthy AI — these are all part of Ethereum's mission. https://t.co/51UfMsxk5o pic.twitter.com/TynzSuzmhX

— Ethereum Foundation (@ethereumfndn) November 3, 2026

In his Devcon 8 keynote, Buterin tied Ethereum’s mission to six goals, according to the Ethereum Foundation (EF). They range from a formally verified operating system and open silicon to self-sovereign health tech and trustworthy AI. Free discourse and private communication also made the list.

We need to be able to trust our operating systems. We need to be able to trust our hardware. We need to be able to trust the things that are most relevant to our health.

Vitalik Buterin, via Devcon

Ethereum already counts more than 1 million developers across its history. Devcon 8 runs through November 6, and Buterin’s warning adds AI to the threats facing the network’s cryptography.