O maior roubo do mundo cripto? Hackers cunharam 1 bilhão de dólares em DOT, mas só conseguiram 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, but due to severe market liquidity shortage, they only cashed out about $237,000.

Cryptocurrency attack incidents are emerging endlessly, 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, due to serious liquidity shortages, they only received about $237,000 worth of Ether.

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 TokenGateway.

Image source: X/@OnchainLens

Cross-chain bridges have always been the most vulnerable link in blockchain architecture because they hold the management rights 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 zero,” which means 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 rights, the attacker minted 1 billion DOT tokens in a single transaction, and through Odos Router V3, deposited these tokens into the DOT-ETH trading pool on Uniswap V4. After multiple exchanges at slightly different prices, they ultimately withdrew about 108.2 ETH.

“Liquidity shortage” becomes a protective shield

In financial markets, “liquidity shortage” is usually the headache of whales and large investors, but ironically, this liquidity shortage became an invisible shield this time, 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 be less than 1 cent.

On 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 once 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 bridge tokens.

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

Image source: X/@CertiKAlert

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