Curve, a stablecoin exchange at the heart of decentralized finance (DeFi) on Ethereum, has been the victim of an exploit according to a tweet from the project. Upwards of $100 million worth of cryptocurrency are at risk due to a “re-entrancy” bug in Vyper, a programming language used to power parts of the Curve system. Several stablecoin pools on the platform — used for pricing and liquidity on a number of different DeFi services — have been drained by hackers so far.