Polkadot Hyperbridge Exploit: 1 Billion DOT Minted and Sold

On April 13, 2026, a vulnerability in the Hyperbridge gateway contract on Ethereum allowed an attacker to mint 1 billion unauthorized Polkadot (DOT) tokens. The exploit was facilitated by forging messages to gain administrative control over the bridged DOT token contract. The attacker subsequently sold the minted tokens for approximately $237,000 worth of Ether. This incident specifically affected DOT tokens bridged to Ethereum, while the native DOT and Polkadot ecosystem remained secure. The Hyperbridge protocol has been paused for investigation and remediation. The exploit highlights ongoing vulnerabilities in cross-chain interoperability solutions. The incident has raised concerns about the security of decentralized finance (DeFi) infrastructures. Security firms CertiK and BlockSec are investigating the attack vector and its implications.

Key Points: • 1 billion unauthorized DOT tokens were minted and sold due to a Hyperbridge exploit. • The attack did not affect the native Polkadot ecosystem or DOT bridged through other protocols. • Hyperbridge has been suspended for investigation following the incident.