Ethereum co-founder Vitalik Buterin has backed a new warning that advances in artificial intelligence could undermine the cryptography used in today’s blockchains before quantum computers do. Buterin was responding to a post from Ethereum researcher Justin Drake on Wednesday urging the industry to prepare for “bunker mode,” as AI could eventually make it possible to break the elliptic curve digital signature algorithm (ECDSA) used to secure cryptocurrency wallets. Drake said users should begin a...