Harmony (ONE Token) (2026) — Crypto Hack
Chain Rollback PlannedAn attacker forged the mint of 4 billion ONE tokens (~26% of supply) on the Harmony layer 1 blockchain, causing ONE to fall 40%. Harmony planned a chain rollback to August 11 checkpoints, discarding 109,000+ transactions.
Summary
An attacker forged the mint of 4 billion ONE tokens (~26% of supply) on the Harmony layer 1 blockchain, causing ONE to fall 40%. Harmony planned a chain rollback to August 11 checkpoints, discarding 109,000+ transactions.
How It Was Compromised — Layer 1 via Forged Token Mint
The Harmony layer 1 blockchain suffered a supply inflation attack on August 12, 2026, when an attacker forged the mint of 4 billion ONE tokens, representing approximately 26% of the total supply. The ONE token fell 40% in value following the attack. In response, Harmony announced plans for a chain rollback to the August 11 checkpoints, which would discard over 109,000 transactions that occurred after the attack. The incident raised significant questions about the security of layer 1 blockchain minting mechanisms and the controversial practice of chain rollbacks. Note: This is distinct from the 2022 Horizon Bridge hack affecting Harmony.
Fund Flow & Laundering Analysis
Forged ONE tokens spread across the Harmony network before the rollback could be executed, with the attacker attempting to move funds across bridges before the chain could be halted.