The Horizon Bridge, which enables token transfers between Harmony and the Ethereum network, Binance Chain and Bitcoin, has been hacked, resulting in the loss of $100 million in altcoins.
In a tweet, the company wrote:
1/ The Harmony team has identified a theft occurring this morning on the Horizon bridge amounting to approx. $100MM. We have begun working with national authorities and forensic specialists to identify the culprit and retrieve the stolen funds.
It went on to identify the culprits' ETH address while also noting that the heist “does not impact the trustless BTC bridge; its funds and assets stored on decentralized vaults are safe at this time” and that it has already notified the exchange, putting the Horizon bridge to a halt to prevent further transactions, adding that “the team is all hands on deck as investigations continue. We will keep everyone up-to-date as we investigate this further and obtain more information.”
So far, the culprits have managed to steal Frax (FRAX), Wrapped Ether (WETH), Aave (AAVE), Sushi (SUSHI), Frax Share (FXS), AAG (AAG), Binance USD (BUSD). Dai (DAI), Tether (USDT), Wrapped BTC (WBTC), and USD Coin (USDC).
The heist comes following a set of concerns issued over the soundness of Horizon’s multisig wallet on Ethereum, which requires just two, out of a total of four, to retrieve the funds.
In April, the capital crypto-focused venture fund Ape Dev warned on Twitter that the low number of required signers would leave the bridge open for “another 9-figure hack.”
Co-founder of Ethereum, Vitalik Buterin likewise questioned the rationale of the token bridges that become vulnerable to hacks due to their increasing amount.
The concerns of both materialized, with culprits successfully exploiting Meter’s token bridge, Axie Inifinity’s Ronin Bridge, the Wormhole Bridge, and Horizon Bridge over the past five months. Combined, the losses amount to over $1 billion.
