Harmony to revert chain to Aug. 11 after ONE token exploit

Harmony announced Monday it will roll its blockchain back to Aug. 11, reverting validators to blocks recorded at 23:25 UTC. The rollback will remove 109,126 regular transactions and 315 staking transactions. Validators will load replacement databases and begin producing new blocks from the next heights.

The network took the step after investigators found unauthorized ONE tokens had been minted and moved to exchanges and other services. Harmony had been weighing a rollback after reports of forged tokens emerged last week. Investigators traced nearly all forged tokens to specific wallets or service boundaries and are tracking their movement.

Engineers determined that selectively restoring transactions would be unsafe because account balances, smart contract states, nonces and other chain conditions would differ on a replacement chain. To rebuild a consistent ledger, validators will use databases that reflect the chain state at the rollback checkpoint and continue block production from the subsequent heights.

Investigators are coordinating with exchanges, bridge operators and law enforcement to trace the forged supply, recover funds where possible and block deposits linked to the exploit. At the time of the announcement the token’s market capitalization was about $10.8 million.

Rollbacks that reverse confirmed blockchain activity are uncommon. Earlier this year another network prepared a chain reorganization after a consensus flaw was exploited and miners began building a competing chain that could reverse prior confirmations.

Developers and node operators have not provided a precise timeline for completing the rollback or fully restoring network operations. The process will begin from the specified checkpoint and proceed once validators adopt the replacement databases.