$815K Breach Rocks Alephium TokenBridge with Off-Chain Flaw Exploitation

Alephium's TokenBridge was hit by a massive attack on May 30, resulting in the loss of approximately $815,000. The attackers exploited an off-chain backend flaw to drain funds from both Ethereum and BNB Chain within seven minutes.

The hackers minted 13.76 million unbacked wrapped ALPH tokens, exceeding the bridge's entire prior wrapped supply. Alephium has denied any involvement of stolen guardian keys in the breach, attributing it to a private fork of the Wormhole messaging system with only four signers.

Alephium has halted the bridge and promised a recovery path for users whose coins stayed locked inside. The team is weighing every option to make affected users whole, with a full postmortem due this week.