CoW Swap Hack

TOTAL LOST $180K
Low Access Control Attacks ethereum

What happened

Quick Summary

On Feb. 7, the CoW Swap fee manager contract was drained of worth 160k $USD.

Details of the Exploit

The CoW Swap uses external resolvers for swap routing to find the best exchange way. The solver also receives a protocol fee. granted approval for the malicious contract.

27 Feb the malicious contract was approved by the whitelisted solver. After that, the hacker received an opportunity to drain the fee collector contract.

Block Data Reference

Exploit TX:

https://etherscan.io/tx/0x90b46860…24379b

Malicious call:

https://etherscan.io/tx/0x92f906bc…b3bfc1

Exploiter:

https://etherscan.io/address/0xc0e82c1e…5266ff

https://etherscan.io/address/0x94b6f400…95658c

Case & protocol details

Classification Exchange (DEX) / Access Control
Protocol Type Exploit/Other
Smart Contract Language Solidity
Official Website cow.fi/
Protocol Twitter/X @CoWSwap

Evidence & learning

Attack pattern

Compare incidents →
Access Control Attacks Delegatecall & Call Injection Attacks

Sources and on-chain records

Browse all hacks

Other incidents recorded with the same attack technique.

Aave $56K
Chainge Finance $716K
BasketDAO $1.2M
Brahma Finance $90K

Practice this exploit pattern safely

Work through hands-on labs covering real exploit mechanics, review techniques, and defensive patterns.

Start Free Trial Explore attack classes