Sandwich Attack
Last updated 17 October 2026Last verified 17 October 2026
What is a sandwich attack in crypto?
An MEV strategy where a bot places one transaction just before and one just after a victim's trade, profiting from the price move the victim's order creates. Most visible on illiquid pairs with high slippage tolerance. Setting a tight slippage limit is the primary user defense, at the cost of more frequent transaction failures during volatile periods.
TradFi equivalentCalled front running on-chain, but order anticipation in the regulatory sense, since the bot owes the trader no duty and the order was public before it was acted on. It trades ahead and closes behind, capturing the move the order itself creates.