Cysic has suspended its cross-chain bridge following an unauthorized token issuance on BNB Smart Chain. An attacker exploited a processing flaw to mint 10 million CYS tokens on Saturday at 12:31:38 UTC, according to an incident report the company posted on Sunday.
Preliminary findings indicate the breach stemmed from unauthorized access to a database supporting the bridge. Cysic added the recipient address to the token contract's blacklist within about 76 minutes of the incident, with approximately 2.8 million CYS remaining at that address with transfers restricted.
The company stated that the incident was limited to bridge message processing and minting operations, with no impact to the mainnet or other operational systems. "The incident did not result in the theft or unauthorized transfer of existing CYS or other assets held in user wallets," Cysic said.
CYS tokens coordinate incentives for users, compute providers, governance participants and contributors across Cysic's network. The company noted that the quantity minted alone does not establish the financial impact of the incident, as token transfers, swaps and actual losses remain under investigation.
Cysic has engaged a security firm to investigate the breach and plans to publish a follow-up report once the current investigation phase concludes.
