Crypto Investor Loses $50 Million in DeFi Swap Slippage Mishap

Aave, a leading decentralized lending protocol on Ethereum, integrates CoW Protocol into its interface, allowing users to swap collateral assets directly. The case underscores the risks of user-authorized DeFi transactions: large orders placed in illiquid markets can execute far from prevailing prices, and even front-end warnings may not prevent irreversible losses.

On March 12, 2026, the user swapped about $50.43 million of aEthUSDT for aEthAAVE through Aave’s interface. After manually accepting a warning of roughly 99.9% price impact, the user received only about 327 tokens worth $36,000. Aave launched Aave Shield on March 17, blocking swaps with price impact above 25% by default.