Hackers stole $100 million worth of cryptocurrency from Horizon, the blockchain bridge platform developed by startup Harmony.
Blockchain bridges are used for users to transfer assets and data back and forth between different blockchain networks. In recent times, these platforms have become the main target of hackers due to many security holes in their underlying code.
This attack follows the chain of previous attacks targeting bridge platforms, previously Ronin Network ($600 million loss) and Wormhole ($320 million).
Details of the attack have not yet been released. However, Harmony, the developer of Horizon, said that they discovered the incident on the morning of June 22, along with a personal account being suspected as the culprit.
“We have begun to coordinate with the authorities and experts to identify the culprit and recover the stolen assets,” quoted a statement from Harmony.
Accordingly, the company is working with the FBI and many other cybersecurity companies to investigate the attack.
Blockchain bridges play an important role in the shared decentralized finance (DeFi) space. In the case of Horizon, the platform allows users to send tokens from the Ethereum network to Binance Smart Chain.
According to Jess Symington, research lead at blockchain analytics firm Elliptic, bridging platforms “have massive liquidity,” making them “an attractive target for hackers.”
“In order for users to use bridges to move assets back and forth between different networks, assets are locked on one blockchain, and unlocked or minted on another. That process causes the service to contain a large amount of cryptocurrency,” Symington said.
Although Harmony did not disclose exactly how the hackers got in, security concerns for Horizon have been voiced by an investor since April.
Horizon uses a multi-sig wallet, 2 signatures are required to initiate a transaction. Some experts speculate that hackers have “compromised private keys”, stolen passwords, thereby gaining access to digital wallets.
This theft continues the chain of negative news surrounding the crypto sector. A few weeks ago, crypto lenders Celsius and Babel Finance had to freeze withdrawals and transfers after asset values plummeted, leading to insolvency fears. Next, crypto hedge fund Three Arrows Capital is also facing the risk of default with a $600 million loan from brokerage Voyager Digital.