DeFi Users Fall Prey to Sandwich Attacks: New Protocols Offer Fresh Solution

DeFi users have long believed they interact directly with automated market makers when swapping tokens on Uniswap or SushiSwap. However, in 2022, this was only broadly true. A user would sign a transaction that entered the public mempool, where validators would include it in a block and the AMM's constant-product formula determined the price.

This model had a problem: the public mempools are 'hunting grounds' for MEV bots, which monitor pending transactions and execute sandwich attacks. They buy before your trade pushes the price up, then sell after, extracting value from the spread. By 2023, Flashbots estimated that MEV extraction on Ethereum exceeded $600 million in cumulative profit, with a significant share coming from sandwich attacks on retail swaps.

Intent-based protocols restructured this flow by having users sign an intent: a declarative statement of the desired result. A network of solvers then competes to fill that intent at the best possible price, off-chain, without exposing the order to the public mempool.