IoTeX has reported a security breach on its cross-chain bridge, ioTube, on February 21. The attack exploited a vulnerability in the Ethereum-side validator contract, allowing the attacker to maliciously upgrade the contract and mint 410 million CIOTX tokens. Approximately $4.4 million in bridge reserve assets were transferred. IoTeX confirmed that its L1 mainnet and users' on-chain assets remain unaffected. Most of the minted tokens have been locked or frozen, with only about 0.4% at risk. The ioTube bridge has been suspended, and compensation and audit plans will be announced later.