What happened
Lendf.Me, dForce's Ethereum lending protocol, was drained through an ERC-777 reentrancy flaw involving imBTC. The attacker inflated recorded imBTC collateral through the token's callback behavior, then borrowed assets from more than ten liquidity pools. dForce later confirmed that all stolen assets were recovered and users were made whole.
Lendf.Me allowed a callback-capable ERC-777 token to invoke external control flow during deposit processing without comprehensive reentrancy protection. Its balance-accounting flow did not safely commit state before the token transfer interaction, enabling stale collateral values to overwrite the withdrawal result.
Case & protocol details
Attack Timeline
The attacker interacted with Lendf.Me using imBTC, an ERC-777-compatible token. During token-transfer processing in supply(), the ERC-777 callback enabled a reentrant withdraw() before Lendf.Me finalized the user's balance update. The reentrant path withdrew collateral while the outer supply() call later wrote a stale, higher balance back to storage.
Repeating the cycle inflated the attacker's recorded collateral, allowing borrowing of the protocol's available WETH, stablecoins, BTC-related assets, and other tokens. The related April 18 Uniswap imBTC incident used the same callback family but was a separate exploit and must not be conflated with this lending-market drain.
Funds Recovery
Recovered
$25.2M
Net Loss
$0
Evidence & learning
Attack pattern
Compare incidents →Proof of concept
1 availableSources and on-chain records
- report Post-Mortem peckshield.medium.com
- report Report slowmist.medium.com
- report Post-mortem medium.com
- report Post-mortem medium.com
- report Post-mortem medium.com
- transaction Transaction etherscan.io
Practice this exploit pattern safely
Work through hands-on labs covering real exploit mechanics, review techniques, and defensive patterns.