How MEV Extracted Value from the Public Mempool
When you submit a trade on a decentralized exchange (like Uniswap), your transaction waits in the public mempool before being included in a block. Specialized algorithms (MEV searchers) monitor this queue and pay high priority gas fees to frontrun your trade, extracting value directly from your execution.
The Sandwich Attack Anatomy:
1. Bot spots your buy order in the mempool with 1% slippage.
2. Bot buys before you, pushing the price up to your maximum slippage limit.
3. Your order fills at the worse price.
4. Bot immediately sells at the higher price, pocketing the difference.
2. Bot buys before you, pushing the price up to your maximum slippage limit.
3. Your order fills at the worse price.
4. Bot immediately sells at the higher price, pocketing the difference.
How to Protect Your DEX Swaps from MEV Exploitation
- Tighten Slippage Tolerance: Never leave slippage set to default (e. G., 2% or 3%). Set slippage to 0.1% to 0.5% on liquid pairs to reduce the profit buffer for sandwich bots.
- Route Through Private RPCs: Add private endpoints like Flashbots Protect (`rpc. Flashbots. Net`) or MEV-Blocker to your browser wallet. Private transactions go directly to block builders without appearing in the public mempool.
- Use CoW Swap / Intent-Based DEXs: Batch-auction protocols match trades peer-to-peer off-chain, protecting orders from frontrunning.