Glossary
Harmony Horizon Bridge Hack (2022)
The June 2022 exploit that drained ~$100M from the Harmony Horizon Bridge — compromised 2-of-5 multisig signatures attributed to North Korea's Lazarus Group.
The Harmony Horizon Bridge used a 2-of-5 multisig to authorize withdrawals between Ethereum and the Harmony chain. On June 23, 2022, attackers compromised two of the five signing keys — sufficient to authorize any withdrawal — and drained roughly $100 million in assets in a series of transactions.
The US Treasury later attributed the attack to North Korea's Lazarus Group. Harmony attempted a controversial "recovery" proposal involving minting new tokens to backstop losses; the proposal was ultimately abandoned amid community pushback. The incident contributed to Harmony's broader decline.