Security

Harmony

Billion

<h3 id="summary">Summary:</h3>
<ul>
 <li>Harmony confirmed that an exploit allowed an attacker to mint four billion ONE tokens, sending most of the unauthorized supply to cryptocurrency exchanges.</li>
 <li>ONE dropped 34% as Harmony coordinated with exchanges, developed a patch, and evaluated rollback options during the investigation into the breach’s cause.</li>
 <li>Harmony previously suffered the Horizon bridge hack in 2022, with the FBI later linking a nearly $100M theft to North Korean groups.</li>
</ul>
&nbsp; 
Layer 1 blockchain Harmony has confirmed an exploit that allowed an attacker to mint 4 billion ONE tokens without authorization. <a href="https://x.com/the_juice_berg/status/2087353885765620127" rel="noopener noreferrer nofollow">According to X user Juiceberg</a>, the attacker used empty blocks to create the tokens before moving most of them toward <a href="https://36crypto.com/centralized-vs-decentralized-cryptocurrency-exchanges/" rel="noopener noreferrer nofollow">cryptocurrency exchanges</a>. 
Juiceberg reported that roughly 97% of the unauthorized ONE supply had already reached exchanges or remained inside deposit wallets. Meanwhile, the attacker retained approximately 115 million ONE on-chain, representing about 2.9% of the reported four billion minted tokens. 
Harmony’s totalSupply endpoint also failed to immediately reflect the additional supply, raising further concerns about the network’s accounting mechanisms. ONE dropped about 34% over 24 hours as traders reacted to the unexpected increase in the cryptocurrency’s circulating supply. 
The token traded near $0.0008, placing the four billion unauthorized ONE tokens at an estimated value of $3.2 million. Harmony acknowledged the exploit through its official X account and directly addressed the information shared by Juiceberg. 
Moreover, the blockchain project reported working with relevant cryptocurrency exchanges to stop transfers and freeze funds connected to the incident. Harmony is also preparing a software patch while examining possible measures for limiting the damage caused by the unauthorized token creation. 
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<h2 id="harmony-evaluates-rollback-as-investigation-targets-exploit-s-root-cause">Harmony Evaluates Rollback as Investigation Targets Exploit’s Root Cause</h2>
Harmony is considering rollback options as developers investigate the technical weakness that enabled the unauthorized creation of billions of ONE tokens. However, the project has not disclosed the specific vulnerability responsible for the breach or explained how the attacker accessed it. 
<div class="embed-x">
 <blockquote class="twitter-tweet">
 We are working with our team and appropriate exchanges to stop and freeze the funds. 
 We are working on a patch and rollback options. 
 Will update when we have new information. <a href="https://t.co/XB0nCwTAyN" rel="noopener noreferrer nofollow">https://t.co/XB0nCwTAyN</a> 
 — Harmony <img src="https://s.w.org/images/core/emoji/17.0.2/72x72/1f499.png" alt="💙"> (@harmonyprotocol) <a href="https://x.com/harmonyprotocol/status/2087395174263705704?ref_src=twsrc%5Etfw" rel="noopener noreferrer nofollow">August 12, 2026</a> 
 </blockquote>
</div>
Investigators are also examining why the totalSupply endpoint failed to immediately register the four billion additional tokens created during the attack. Additionally, exchange cooperation remains important because Juiceberg reported that most of the unauthorized supply had already reached exchange-linked addresses. 
A successful freeze could prevent some remaining tokens from entering circulation, although Harmony has not disclosed how many exchanges have secured. The exploit adds another major security incident to Harmony’s history, which includes the costly compromise of its Horizon cross-chain bridge. 
<h2 id="previous-horizon-bridge-hack-remains-part-of-harmony-s-security-history">Previous Horizon Bridge Hack Remains Part of Harmony’s Security History</h2>
Hackers targeted Harmony’s Horizon bridge in June 2022 and stole cryptocurrency assets valued at nearly $100 million. The stolen assets included Ethereum and several stablecoins held within infrastructure supporting cryptocurrency transfers across different blockchain networks. 
Security researchers linked the breach to compromised private keys associated with the bridge’s multi-signature wallet and transaction authorization process. Moreover, the FBI attributed the Horizon attack to <a href="https://36crypto.com/north-korean-hackers-deploy-private-ai-systems-to-target-crypto-firms/" rel="noopener noreferrer nofollow">North Korean hacking organizations</a> Lazarus Group and APT38 in January 2023. 
Harmony launched its mainnet in 2019 as a proof-of-stake blockchain designed to provide faster and cheaper transactions than Ethereum. ONE serves as Harmony’s native cryptocurrency and supports transaction fees, staking activities, and governance participation throughout the blockchain ecosystem. 
Harmony’s investigation now centers on identifying the vulnerability, securing affected funds, and determining whether a network rollback becomes necessary. 
Also Read:&nbsp;<a href="https://36crypto.com/crypto-market-update-bitcoin-slips-below-64k-as-bnb-xrp-and-doge-rally/" rel="noopener noreferrer nofollow">Crypto Market Update: Bitcoin Slips Below $64K as BNB, XRP and DOGE Rally</a> 
The post <a href="https://36crypto.com/harmony-confirms-one-exploit-as-attacker-mints-4-billion-tokens/" rel="noopener noreferrer nofollow">Harmony Confirms ONE Exploit as Attacker Mints 4 Billion Tokens</a> appeared first on <a href="https://36crypto.com" rel="noopener noreferrer nofollow">36Crypto</a>.

Harmony Confirms ONE Exploit as Attacker Mints 4 Billion Tokens

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