Crypto money worth $100 million has been stolen. The Horizon Bridge that connects to the Harmony Layer-1 blockchain has been attacked by crypto hackers.

The hack resulted in the theft of $100 million worth of alternative cryptocurrencies, which are currently being traded for ether (ETH).

Another cryptocurrency bridge was hacked today. A crypto bridge is an app that allows users to trade currencies between different blockchains.

Interoperability between the Ethereum, Binance Smart Chain (BSC), and Harmony blockchain networks can be achieved through the use of the Horizon Bridge.

It's possible that this breach may validate worries that the community had previously voiced regarding the reliability of two of the four multisigs that are supposed to safeguard the bridge.

Harmony Confirms Attack

Harmony confirmed the attack by the crypto hackers on its Horizon Bridge yesterday.

Earlier on Twitter, the company tweeted, "The Harmony team has identified a theft occurring this morning on the Horizon bridge amounting to approx. $100MM."

Harmony also stated, "We have begun working with national authorities and forensic specialists to identify the culprit and retrieve the stolen funds."

 The following tweet from the company also clarified that the Bitcoin Bridge and all of its assets that are in decentralized vaults had not been compromised in any way by the attack.

The blockchain company, Harmony, was founded by Stephen Tse in 2018. It is an Effective Proof of Stake (EPoS) blockchain that focuses on security, decentralization, and scalability.

Harmony's Horizon Bridge is a cross-chain platform that allows its users to trade assets such as NFTs, crypto tokens or coins, or move tokens to and from the Binance Smart Chain (BSC), Harmony Blockchain, Ethereum, and other chains.

The crypto hackers amassed multiple kinds of currencies such as Tether (USDT), Wrapped Ether (WETH), Wrapped BTC (WBTC), Binance USD (BUSD), USD Coin (USDC) and many more.

Harmony's Crypto Hack

There were a total of 11 transactions made for a variety of tokens using the bridge between the hours of about 7:08 and 7:26 ET.

The crypto hackers started sending tokens to a different wallet so that they could trade them for ETH on the Uniswap decentralized exchange (DEX).

After that, the actors send the ETH back to the wallet from which they originally obtained the tokens.

According to Blockworks, the company's security team has identified the address used in the attack. The address is reported to have 85,837 ether, which is over $98 million USD.

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Threats to Crypto's Multistig Wallet

Harmony's Horizon Bridge has received a few warnings from developers in the industry.

According to Cointelegraph, "Concerns have previously been expressed as to the soundness of Horizon's multisig wallet on Ethereum, which only requires two out of the four signees to drain the funds."

Ape Dev, the founder of Chainstride Capital, tweeted in April that the low number of required signers would make the bridge vulnerable to hacking that would cost nine figures.

Unfortunately, with the current $100 million crypto hack, it appears that Ape Dev's prediction was accurate.

Furthermore, Cointelegraph also reported that Vitalik Buterin talked about the issues underlying bridges.

In January, he presented the fact that when bridges get exploited, it threatens the liquidity of each chain affected. Buterin also added that the number of token bridges increases, the more it is susceptible to a % attack on its chain.

This is the third significant bridge hack that has occurred this year. Hackers made off with more than $300 million from the Wormhole bridge in February. Meter's token bridge also lost $ 4.4 million.

At the end of March, hackers stole approximately $620 million from Ronin Bridge. Meter's token bridge lost $ 4.4 million.

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