Harmony Protocol was hit by a suspected exploit on Wednesday that led to the unauthorized minting of about 4 billion ONE tokens, roughly 26% of the token’s total supply. The newly created tokens moved through the network and into cryptocurrency exchanges, and ONE fell more than 30% as the selling pressure hit the market. Harmony confirmed the exploit and said it is now working with its team and several exchanges to freeze funds connected to the attack. 

How Attackers Minted 4 Billion ONE Tokens

The exploit appears to have involved the unauthorized minting of ONE through empty blocks. About 4 billion tokens were created without authorization, a figure that on its own equals roughly a quarter of everything in circulation before the attack.

Harmony also shared four specific wallet addresses tied to the exploit, including ONE network addresses and their linked Ethereum counterparts, and has asked exchanges to block and freeze any funds tied to them.

From there, the attacker moved the funds quickly. Around 2.8 billion ONE was transferred to cryptocurrency exchanges, where it could be converted into other assets. ONE fell more than 30% in the hours after the exploit, according to TradingView data.

Source: TradingView, 24H Market Data

The incident echoes other exploits that have hit DeFi protocols in recent months. Arbitrum, for example, froze $71 million in stolen Kelp funds after a similar exploit, showing that quick coordination with exchanges and validators can limit how much of the stolen amount actually reaches the open market.

What This Means for ONE Holders

Holders now face a token whose supply just grew by roughly a quarter overnight, with no guarantee that a rollback will reverse it. Harmony has said only that it is working on a patch and rollback options and will update the community once it has more information, and until that decision is made, the extra tokens sitting in exchange wallets remain a standing risk to price.

If you’d like to follow the exploit and any rollback decision, and the latest DeFi security news, you can check our news hub.

Whether Exchanges Freeze the Stolen ONE in Time

The bigger question now is how much of the 2.8 billion ONE moved to exchanges gets frozen before it can be sold. If a large share slips through, ONE could face further selling pressure beyond the 30% drop already seen. Harmony has asked exchanges to act on the four wallet groups it flagged, and how many comply in the coming days will shape where the token’s supply and price settle.

What this means for you: If you hold or are considering buying ONE, know that its circulating supply just jumped overnight, and prices could keep moving depending on how much of the stolen ONE exchanges manage to freeze. 

This article is for informational purposes only and does not constitute financial advice. Do your own research before making any investment decisions.