Cysic discloses cross-chain bridge attack, 10 million CYS illegally minted on BNB Chain

On October 18, the Cysic Foundation issued a security incident announcement stating that the Cysic cross-chain bridge suffered a security incident on October 17. The attacker exploited unauthorized access to a database related to the bridge service and a processing logic vulnerability to illegally mint 10 million CYS on BNB Chain. The incident occurred at 12:31:38 (UTC) that day.

Cysic stated that the incident only affected the bridge's message processing and token minting functions, did not affect the Cysic mainnet or other operational systems, and no existing user assets were stolen. The project team has suspended the cross-chain bridge service and blacklisted the involved receiving address in the CYS token contract at 13:47:52 (UTC) that day. Transfers of the roughly 2.8 million CYS remaining at that address are now restricted. Cysic has engaged a professional security firm to investigate the attack path and trace the flow of funds. The actual loss amount and the subsequent movement of the tokens are still under review, and the cross-chain bridge will be restored only after the security review is completed.