
Briefing
Cork Protocol, a decentralized finance platform, endured a sophisticated $12.1 million exploit on July 11, 2025, stemming from a manipulation of its Uniswap V4 hook logic. The attacker leveraged fraudulent swap conditions within the beforeSwap hook to bypass critical access controls, enabling the unauthorized issuance of legitimate Cover Tokens. This incident underscores the profound risk posed by complex smart contract integrations when robust validation and economic simulations are not adequately implemented, resulting in a significant loss of 3,761 wstETH.

Context
Prior to this incident, the DeFi ecosystem has increasingly faced economic-logic exploits that weaponize the flexibility of smart contract architectures rather than relying on basic coding bugs. Protocols integrating advanced features like Uniswap V4 hooks, designed for custom pool logic, often introduce new attack surfaces if not rigorously audited for behavioral and economic edge cases. The prevailing risk factors include insufficient identity validation within smart contracts and a lack of comprehensive economic simulations during security assessments.

Analysis
The Cork Protocol exploit targeted the platform’s Uniswap V4 hook logic, specifically the beforeSwap function. The attacker initiated the incident by creating a malicious market using a genuine Depeg Swap token from another pool. This allowed the attacker to manipulate Cork’s hook, effectively bypassing the intended access controls.
By leveraging these fraudulent swap conditions, the attacker gained unauthorized ability to issue legitimate Cover Tokens, ultimately draining approximately 3,761 wstETH, valued at $12.1 million. The funds were subsequently laundered via Tornado Cash.

Parameters
- Protocol Targeted ∞ Cork Protocol
- Attack Vector ∞ Uniswap V4 Hook Manipulation / Access Control Bypass
- Financial Impact ∞ $12.1 Million (3,761 wstETH)
- Blockchain(s) Affected ∞ Ethereum (implied by wstETH and Uniswap V4)
- Date of Incident ∞ July 11, 2025
- Attacker’s Method ∞ Fraudulent swap conditions via beforeSwap hook
- Funds Laundered Via ∞ Tornado Cash

Outlook
Immediate mitigation for users involves exercising extreme caution with protocols employing complex hook logic and ensuring that any integrated systems have undergone thorough, multi-layered audits. This incident will likely drive a renewed focus on auditing not just for code syntax, but for comprehensive behavioral logic and economic simulations in DeFi protocols. Similar protocols utilizing Uniswap V4 hooks must urgently review their validation mechanisms for hooks and oracles, treating all backup and hedging tools as primary attack surfaces to prevent contagion risk.
Signal Acquired from ∞ Cybantage