Blockchain bridge Wormhole has confirmed that roughly $320 million worth of cryptocurrency has been stolen following a hack discovered on Wednesday.
Wormhole is a bridge that connects various blockchains, including Ethereum, Solana, Terra, Binance Smart Chain, Polygon, Avalanche, and Oasis. One of its main features is a token bridge that allows users to bridge wrapped assets between these blockchains.
The service announced on Wednesday that the Wormhole network had been shut down “for maintenance” as it had started looking into a potential exploit.
The attacker apparently used an exploit that has since been patched to mint 120,000 wrapped Ethereum (wETH) on the Solana blockchain, much of which was then transferred to the Ethereum blockchain. The 120,000 wETH was worth roughly $320 million at the time of the attack.
Wormhole developers have apparently offered the attacker a $10 million bug bounty through a “whitehat agreement” if they return the stolen cryptocurrency.
Wormhole has promised to share a detailed incident report. In a few messages shared on Twitter on Thursday, the service said it had restored all funds and the network. The funds were restored with the help of Jump Crypto, the crypto division of Jump Trading Group.
This appears to be the second-largest cryptocurrency heist. The largest took place in August 2021, when Poly Network announced that someone had stolen roughly $600 million worth of cryptocurrency. However, in that case, nearly all of the stolen funds were returned days later.
*updated to add that the funds were contributed by Jump Crypto
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