Harmony Plunges 10% After Horizon Ethereum Bridge Hacked For $100 Million

Hackers have struck layer 1 blockchain Harmony's Horizon bridge, stealing $100 million in cryptocurrency.

The exploit was revealed in a tweet in the early hours of Friday morning. The Harmony team revealed that it had "identified a theft occurring this morning on the Horizon bridge amounting to approx. $100MM." It went on to add that the address of the culprit had been identified and that the Harmony team are working with "national authorities and forensic specialists" to retrieve the stolen funds.

In a follow-up tweet, Harmony noted that it is "working around the clock" alongside the FBI and "multiple cyber security firms."

Tokens including Wrapped Ethereum (WETH), AAVE, SUSHI, DAI, Tether (USDT) and USD Coin (USDC) have been stolen from the bridge and swapped for Ethereum.

Harmony stated that it has stopped the Horizon bridge to prevent further transactions, and noted that the exploit does not affect its trustless BTC bridge. "Its funds and assets stored on decentralized vaults are safe at this time," said the Harmony team.

Harmony's ONE token has plunged by over 10% on the day, per data from CoinMarketCap, and is currently changing hands for $0.02416.

Cross-chain bridge hacks

Harmony aims to solve the "blockchain trilemma" of balancing scalability with security and decentralization. The cross-chain Horizon feature enables crypto holders to move between Harmony's network and the Ethereum network, Binance Chain and Bitcoin.

This is the latest in a series of exploits that have stolen hundreds of millions of dollars from cross-chain bridges in recent months. In January, Qubit Finance's bridge was hacked for $80 million, and just a month later, the Wormhole bridge was hacked for $320 million.

Both hacks were dwarfed, however, by the March 2022 hack of Axie Infinity's Ronin bridge, which drained $622 million in Ethereum and USDC.