AFX Protocol bridge exploited; $24.15M stolen

AFX Protocol, a decentralized perpetual exchange on Arbitrum, reported a loss of $24.15 million on Wednesday after an attacker exploited one of its cross-chain bridges.

Security monitor Blockaid detected the exploit at 9:30 p.m. UTC and flagged a suspicious bridge transaction. On-chain traces published by Lookonchain show the attacker moved 24.15 million USDC to Ethereum and converted it into ETH, buying 12,467 ETH at an average price of $1,937.

Offchain Labs co-founder Stephen Goldfeder confirmed the transaction originated from a third-party protocol and said Arbitrum’s native bridge was not compromised. He wrote on X: “We’re aware of a report of a bridge hack on Arbitrum and are investigating. We can confirm that the transaction in question originated from a third-party protocol, and the Arbitrum native bridge has not been hacked or exploited in any way.”

Cross-chain bridges transfer tokens between separate blockchains by locking assets on one chain and releasing equivalent tokens on another chain. Bridges typically hold large token balances and depend on smart contract logic and external components to move funds between networks.

AFX Protocol has not published a detailed post-mortem. Security teams and blockchain analysts are tracing the transactions to determine the method of exploitation and whether any of the stolen funds have been moved through additional on-chain steps.

Further technical details, mitigation measures or any recovery of funds will depend on the outcome of forensic analysis and subsequent on-chain activity by the attacker.