Harvest Finance
- Project: Harvest Finance
- Exploit_type: Price Oracle Manipulation (Flash Loan Attack)
- Loss: ~$33.8 million
- Entry_point: withdraw() function in the fUSDT and fUSDC vaults
- Exploit_vector: Manipulated Curve pool prices via flash loans to withdraw more than deposited
- Severity: Critical
- Attack_steps:
- Attacker took a large flash loan from Uniswap to obtain capital.
- They swapped funds repeatedly in the Curve Y pool to manipulate the price of USDT/USDC.
- This manipulation caused Harvest’s internal price oracle to report inflated vault token values.
- Attacker deposited stablecoins into Harvest’s fUSDT and fUSDC vaults at manipulated high prices.
- Immediately withdrew funds after manipulation reverted, extracting excess value.
- Repaid the flash loan and routed profits through Tornado Cash for obfuscation.
- Impact: ~$33.8M drained from Harvest vaults (mostly USDT and USDC)
- Exploitability: High
- Root_cause: Reliance on manipulable on-chain price data without time-weighted average price (TWAP) or oracle safeguards
- Resource:Link