There’s no customer service hotline to call when you make a mistake. One trader learned this lesson the hard way after making what appears to be one of the most devastating mistakes in recent Ethereum history.
According to on-chain data, an unknown user traded $50.4 million $USDT for only 35,900 $AAVE tokens, a catastrophic transaction that resulted in an instant loss of over $50 million.
Aave CEO Stani Kulechov confirmed the incident on
Earlier today, a user attempted to purchase $AAVE using $50 million $USDT via the Aave interface.
Given the unusually large size of the single order, the Aave interface, like most trading interfaces, warned the user of extraordinary slippage and required confirmation via a checkbox.…
— Stani.eth (@StaniKulechov) March 12, 2026
$50 million for a phone
Most decentralized exchanges operate on an automated market maker (AMM) model, relying on liquidity pools. The price of an asset in a liquidity pool is determined by a mathematical formula based on the ratio of the two tokens in that specific pool.
User dropped $50.4 million $USDT in the pool and emptied his $AAVE reserves. The mathematical curve has aggressively driven the price of $AAVE within this specific pool.
Slip tolerance acts like a safety net. It automatically carries out a transaction if the executed price deviates too much from the quoted market price (usually set at a limit of 0.5% or 1%). For this transaction to be successful, the user either manually disabled slippage protection or ignored the DEX’s warning prompts.
“Given the unusually large size of the single order, the Aave interface, like most trading interfaces, warned the user of an extraordinary slippage and required confirmation via a checkbox. The user confirmed the warning on his mobile device and proceeded to trade,” Kulechov explained.
The CoW protocol is specifically designed to protect users from bad transactions, Maximum Extractable Value (MEV) bots, and extreme slippage by using third-party “solvers” to find the most efficient route for a transaction.
“The transaction could not move forward without the user explicitly accepting the risk via the confirmation box. The CoW Swap routers worked as expected and the integration followed industry standard practices. However, even though the user was able to proceed with the swap, the end result was clearly far from optimal,” the CEO noted.
Kulechov said the Aave team will study ways to improve these protections in the future.
