Flash Loan Attack
Exploiting a protocol by borrowing huge uncollateralized sums to manipulate prices or votes within one transaction.
A flash loan attack weaponizes a flash loan: an attacker borrows tens of millions with no collateral, uses that temporary firepower to distort something the target protocol relies on — usually a manipulable price oracle reading from a thin pool — extracts value, then repays the loan, all in a single atomic transaction.
These attacks have drained hundreds of millions across DeFi’s history. Crucially, they exploit design flaws, not stolen keys: the fix is robust oracles (time-weighted or multi-source pricing) and logic that can’t be gamed by momentary price swings. When you read that a protocol lost funds to “price manipulation,” a flash loan was usually the weapon.