Sandwich Attack

A Sandwich Attack is a parasitic form of Miner Extractable Value (MEV) in decentralized finance (DeFi) where an attacker "sandwiches" a victim's pending transaction, typically a large swap on a decentralized exchange (DEX), by placing one transaction immediately before it (front-run) and another immediately after it (back-run) to profit from the resulting price movement and cause significant financial loss for the victim. This predatory strategy exploits the transparency of the public mempool and the predictable execution order of transactions to manipulate the price of an asset within a single block, often resulting in high slippage for the targeted user.