Cetus, Part I: Draining liquidity pools for fun and profit

Wow, it’s been a while, we hope you can find it in your heart to forgive us. Turns out, this episode took us a lot of research.So, what happened? At the end of May, Cetus, a dex on the Sui blockchain, faced a crisis. The liquidity pools that provide the exchange with capital were being drained of all their tokens, and fast. Cetus hit the pause button after 15 minutes, but already 200-some million dollars were gone.Looking at the record on the blockchain sets a mystery. A flash swap, a liquidity add, and withdrawals. For those (like us) not steeped in this world, this is standard defi operations. Don’t worry, we’ll explain. But at the end of the transaction, the liquidity is gone.So what broke? Follow along as we piece it together. Sometimes, when you give a little, you get a lot.