Cysic Halts Bridge After Unauthorized Mint of 10 Million CYS

Cysic paused its cross-chain bridge on Sunday following an incident where an alleged attacker minted 10 million CYS on the BNB Smart Chain the previous day. Initial investigations indicate that a vulnerability in bridge processing allowed unauthorized access to a database that supports the bridge.

Once Cysic implemented transfer restrictions, approximately 2.8 million CYS remained frozen at the recipient address. However, reporting from The Defiant notes that some of the newly minted tokens had already been sold prior to the activation of the blacklist, making the tracing of swaps and transfers a primary focus of the ongoing inquiry.

CYS Blacklist Followed the Unauthorized Mint by About 76 Minutes

According to an incident timeline provided by Cointelegraph, the unauthorized mint occurred at 12:31:38 UTC on Saturday. Approximately 76 minutes later, at 13:47:52 UTC, Cysic added the recipient address to the token contract’s blacklist.

By the time the blacklist took effect, about 2.8 million CYS—representing roughly 28% of the total unauthorized issuance—remained at that address.

Cysic Bridge Exploit: Flaw Was Limited to Bridge Processing

In a statement released on Sunday regarding the CYS hack, Cysic clarified that the issue was confined to bridge message processing and minting. Preliminary findings suggest the breach occurred via unauthorized database access.

The company confirmed that its mainnet and other operational systems were untouched. Additionally, user wallets did not experience any theft or unauthorized transfers of existing CYS or other digital assets.

Consequently, the immediate impact is limited to the unauthorized creation of tokens and the temporary suspension of the bridge. Cysic noted that the database findings remain preliminary as security assessments continue.

CYS Sales Put Token Flows at the Center of the Investigation

Data from onchain records highlighted by The Defiant reveals that certain sales occurred before the blacklist was enforced. As part of its remediation efforts, Cysic is actively reviewing token transfers, swaps, and financial losses.

For token holders, the primary market concern stems from the sale of these newly generated assets before restrictions were put in place. The ongoing review aims to determine the full scope and financial cost of those pre-blacklist transactions.

Project documentation indicates that CYS plays a vital role in coordinating incentives across Cysic’s network for users, compute providers, governance participants, and contributors, meaning the security breach affects a token integrated throughout the entire ecosystem.

Cysic Hires Security Firm for Follow-Up Investigation

To assist with the response, Cysic has partnered with an external security firm and intends to release a comprehensive follow-up report once the current investigation phase wraps up. Initial reviews have centered on database access, bridge processing, and the unauthorized mint.

Key developments for token holders to monitor include the tracking of tokens moved before the freeze, the final calculation of actual losses, and the remediation of the processing flaw. These elements will determine the overall financial damage and the extent of the recovery process.

This article is for information only and is not financial advice.

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