Harmony considers rollback after suspected exploit inflates ONE supply

Harmony is considering rolling back its blockchain after claims that an attacker exploited the network to mint nearly 4 billion ONE tokens, equivalent to about 26% of the token’s supply.

On Tuesday, Harmony said it was working with exchanges to stop and freeze funds. The layer-1 blockchain said it was preparing a patch and evaluating rollback options. It did not confirm the cause, the number of tokens created, or the amount sent to exchanges. 

Cointelegraph contacted Harmony for comment but had not received a response by publication. 

Harmony’s post was in response to an X account called “Juiceberg,” which claimed the unauthorized ONE tokens were minted through empty blocks and that approximately 2.8 billion tokens were quickly funneled to exchanges as ONE’s price fell. 

Juiceberg estimated the attacker had about 115 million ONE remaining onchain, or 2.9% of the amount allegedly minted, with the remainder either sold or held in exchange deposit wallets. Cointelegraph could not independently verify the claims. 

At the time of writing, CoinGecko showed ONE fell 33.9% over the past 24 hours. 

The incident follows Harmony’s June 2022 Horizon Bridge hack, which led to the theft of about $100 million in cryptocurrency. The FBI later attributed the attack to North Korea’s Lazarus Group. 

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