On April 23, 2026, GiddyVaultV3 on Ethereum was exploited for $1.3M via incomplete EIP-712 signature coverage. Unvalidated parameters (aggregator, fromToken, toToken, amount) in SwapInfo structure allowed attackers to manipulate transaction approvals.

The DeFi protocol Giddy’s GiddyVaultV3 contract was exploited, resulting in a loss of approximately $1.3 million. The attack was caused by a design flaw in its authorization validation logic. When using the EIP-712 signature scheme, the contract only validated part of the data within the SwapInfo structure, failing to cover critical parameters such as aggregator, fromToken, toToken, and amount, leading to incomplete signature coverage. The attacker exploited this flaw by replaying a valid signature and crafting malicious transaction parameters: replacing fromToken with the strategy’s LP tokens, setting the aggregator to a contract controlled by the attacker, substituting toToken with a malicious token, and setting the transaction amount to the maximum value. Since these key fields were not included in the signature verification scope, the contract accepted the transaction as valid and executed it. As a result, the attacker successfully transferred out protocol assets, causing a loss of approximately $1.3 million.