Svmuu reports that Aave has published a post-mortem of the April 18 rsETH incident, stating that the rsETH LayerZero V2 cross-chain bridge of liquid staking protocol Kelp accepted a forged message during a cross-chain transfer from Unichain to Ethereum. This caused the adapter on the Ethereum side to release 116,500 rsETH without a corresponding burn on the Unichain side. Aave stated that the attack occurred on a third-party cross-chain bridge infrastructure. However, the attacker deposited the stolen rsETH into 8 Aave V3 positions, borrowing 82,650 WETH and 821 wstETH, which impacted the Aave market.
Aave stated that the attacker's rsETH on Arbitrum has now been burned. The LayerZero OFT adapter has replenished 116,131.72 rsETH in 5 batches, and the asset backing for rsETH has been fully restored. The affected WETH and rsETH markets have returned to normal.