
A hacker exploited a vulnerability in the Hyperbridge gateway on Ethereum to mint 1 billion unauthorized Polkadot (DOT) tokens, causing DOT's price to drop nearly 6% from $1.23 to $1.16 before partially recovering. The attacker used a replay flaw to gain admin control and minted the tokens, but due to low liquidity of bridged DOT on Ethereum, they only cashed out about $237,000 in ether. Polkadot's main network and authentic tokens remain secure. Developers are expected to patch the gateway to prevent future breaches.