O maior roubo no mundo das criptomoedas? Um hacker cunhou 1 bilhão de dólares em DOT, mas só conseguiu roubar 230 mil dólares

Hackers exploit Hyperbridge cross-chain bridge vulnerability to mint 1 billion DOT tokens out of thin air, with a face value of $1.19 billion. However, due to severe market liquidity shortages, they ultimately cashed out only about $237,000.

Cryptocurrency attack incidents are emerging one after another, but cases like this “taking big risks for small gains” are quite rare. Earlier today (13th), hackers exploited a vulnerability in the Hyperbridge cross-chain bridge to mint 1 billion Polkadot (DOT) tokens on Ethereum, with a nominal value of up to $1.19 billion. However, when they tried to sell these tokens, they only managed to exchange them for about $237,000 worth of Ether due to severe liquidity shortages.

It should be clarified that the target of the hacker attack was the “cross-chain bridge smart contract,” so the native DOT tokens on the Polkadot mainnet were not affected. The main cause of this vulnerability was that Hyperbridge’s EthereumHost contract failed to properly verify the authenticity of messages before passing cross-chain messages to the TokenGateway.

Image source: X/@OnchainLens

Cross-chain bridges have always been the most vulnerable link in blockchain architecture because they hold the management permissions of token contracts. Once the verification mechanism is breached, hackers can easily gain the power to mint unlimited tokens.

Attack methods: forging messages, seizing management rights, unlimited minting

On-chain tracking shows that the hacker submitted a forged message via dispatchIncoming and successfully directed it to TokenGateway.onAccept. The system should have verified the authenticity of this message based on the status on the Polkadot chain, but the verification mechanism recorded the promise value as “all zeros,” meaning the verification process was completely bypassed or nonexistent. As a result, the system mistakenly treated this fake message as a legitimate command.

The accepted message immediately executed the changeAdmin function on the bridge Polkadot token contract, transferring admin rights to the attacker’s address. After gaining management control, the attacker minted 1 billion DOT tokens in a single transaction and used Odos Router V3 to deposit these tokens into the DOT-ETH trading pool on Uniswap V4. After multiple exchanges at slightly different prices, they finally withdrew about 108.2 ETH.

“Liquidity shortage” becomes a protective shield

In financial markets, “liquidity shortage” is usually the biggest headache for whales and large investors. Ironically, in this case, the liquidity shortage became an invisible shield, greatly limiting the hacker’s profit potential.

Because the liquidity depth of DOT on Ethereum is extremely limited, it cannot absorb the 1 billion tokens minted out of thin air. When the hacker hurried to sell for cash, severe slippage caused the actual price per token to fall below 1 cent.

In a bridge with deeper liquidity or higher value assets, the same vulnerability could cause losses dozens of times greater. As of the time of writing, DOT’s trading price is about $1.17, down 5% in the past 24 hours.

This incident again illustrates that even if hackers have “unlimited minting rights,” whether they can successfully arbitrage ultimately depends on market liquidity and trading depth. The well-known blockchain security firm CertiK later confirmed the attack and stated that the hacker profited about $237,000 by minting and selling the bridge tokens.

As of now, Hyperbridge has not issued a public statement regarding the hacker incident.

Image source: X/@CertiKAlert

• This article is reprinted with permission from: 《BlockCast》
• Original title: 《The most reckless theft? Hacker mints $1 billion in $DOT, but only steals $237,000 “for this reason”》
• Original author: Block Sister MEL