- A trader on Aave has lost $50 million in a single trade due to extreme slippage caused by his unusually large transaction.
- Founder Stani Kulechov sympathised with the trader and pledged to refund the $600,000 in fees, but says the system “functioned as intended.”
A trader on Aave has lost over $50 million in one of the most disastrous DeFi trades after his unusually large transactions caused a massive price slippage.
On-chain data shows that on Thursday, the trader swapped $50,432,688 in aEthUSDT for aEthAAVE. The first is an interest-bearing token representing USDT deposited on Aave, while the latter represents AAVE tokens deposited on the network’s lending protocol. The trade was placed on the CoW protocol, a swap engine that finds the best price by competing solvers.
However, due to thin liquidity on the relevant pools, the transaction triggered a massive slippage, swapping his tokens for 327 aEthAAVE, worth a little more than $36,000. On-chain data shows that the $50 million lost was captured by arbitrage traders, who made at least $43 million according to BlockSec, and by MEV bots. The protocol generated over $600,000 in fees.
This is unbelievable!
Someone swapped 50.43M aEthUSDT for only 327.241 aEthAAVE ($36K), losing $50.4M.
When trading on Aave, users are clearly warned about high slippage, and they must check the checkbox to confirm the risk of loss before the trade can go through.
But the user… pic.twitter.com/d6gzyTfzK9
— Lookonchain (@lookonchain) March 13, 2026
Slippage in DeFi occurs when an asset’s price changes during a trade’s execution. It’s caused by a transaction that is significantly larger than the available liquidity, or by market manipulation. This can be avoided by splitting large orders into smaller transactions or by setting the maximum slippage tolerance.
Aave Founder: Platform Worked as Intended
Founder Stani Kulechov has responded to the catastrophic trade, sympathizing with the trader and pledging to refund the $600,000 the platform had received as fees.
However, Kulechov maintained that his platform worked as intended. It warned the trader about the slippage and required him to confirm before the trade was executed.
“The user confirmed the warning on their mobile device and proceeded with the swap, accepting the high slippage, which ultimately resulted in receiving only 324 AAVE in return,” Kulechov revealed.
Earlier today, a user attempted to buy AAVE using $50M USDT through the Aave interface.
Given the unusually large size of the single order, the Aave interface, like most trading interfaces, warned the user about extraordinary slippage and required confirmation via a checkbox.…
— Stani.eth (@StaniKulechov) March 12, 2026
He added that the CoW Swap routers “functioned as intended, and the integration followed standard industry practices.”
These kinds of slippages occur in DeFi but are usually much smaller and never make the news, Kulechov says. They showcase the best and worst of DeFi: users are allowed to transact freely without a central entity, but on the flip side, they lack the guardrails offered by traditional platforms. Kulechov called on the industry to develop stronger protections for users to prevent similar cases.
The leading DeFi protocol has been rocked by leadership struggles in recent months, with Kulechov-led Aave Labs being blamed for hindering decentralized operations. BGD Labs and Aave Chan Initiative, both contracted by the Aave DAO to support technical development and security operations, have announced their departures, as CNF reported.
