Usual Hack

TOTAL LOST $43K
Low Arbitration Exploit ethereum

What happened

On May 27, 2025, Usual's USD0++ Investment Vault was exploited through an arbitrage opportunity, leading to a $43,000 loss from the vault itself. The main protocol remained unaffected, with no user funds lost and no pause on the Usual Core Protocol.

The exploit stemmed from a capped mechanism used to unwrap USD0++ into USD0 during deposits into the investment vault. The attacker manipulated this limitation to arbitrage the conversion process, extracting $43,000 from the vault. Since only the vault’s internal funds were impacted and user balances remained untouched, the protocol confirmed that the exploit did not compromise user safety. The affected vault has been isolated and will be reenabled after mitigation steps are implemented.

Tx:

https://etherscan.io/tx/0x585d8be6…f271f8

Case & protocol details

Classification Protocol Logic / Other / Input Validation
Protocol Type Exploit/Other
Smart Contract Language Solidity
Official Website usual.money/

Evidence & learning

Proof of concept

1 available

Sources and on-chain records

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