Imagine a scenario: hackers don't directly steal tokens, but instead deploy a "logic landmine" into the core pool of a mainstream lending protocol via flash loans. This trap is highly covert—any attempt to execute the liquidation function triggers the rollback logic, consuming all the Gas of the executor. The result? The liquidation function becomes completely disabled.

No one can liquidate positions. As the price of the main cryptocurrency drops, bad debts start to pile up like a snowball. The hacker then sends a ransom note: pay 100 million USD, and I will disarm this bomb. Sounds unbelievable? In reality, this is the threat of a Denial of Service (DoS) attack faced by DeFi protocols.

**Why is this kind of attack so dangerous?**

The key lies in the fact that the liquidation function is the lifeline of DeFi lending protocols. Once liquidation is locked, bad debts cannot be processed, and the entire collateral system of the protocol will collapse. The hacker's goal isn't to directly steal funds, but to destroy the core mechanism of the protocol.

**How should protocols defend against this?**

**Gas Management and Auditing**: Lending protocols like Lista DAO must control the Gas consumption of the liquidation function from the source. Contract code needs to undergo rigorous formal verification and auditing to ensure that critical paths do not infinitely expand due to external parameters (such as loop counts or user numbers).

**Emergency Shutdown Mechanism**: Most importantly, implement an emergency mode controlled by the DAO community. When abnormal attacks are detected, governance votes can quickly upgrade the contract logic, bypass polluted functions, or even freeze the hacker's addresses' funds. This acts as the protocol's "emergency button."

**What should users do?**

If you're using a lending protocol and notice that the liquidation function has been disabled for a long time or that execution costs have sharply increased, this could be a red flag. Stay alert to official announcements and consider reducing your exposure. This is not paranoia, but a responsible approach to safeguarding your assets.