Cardano faced a significant disruption over the weekend due to a rare chain split, which was triggered by a malformed transaction. This incident highlights the complexities of maintaining network integrity amid varying software versions among node operators. The publication provides the following information: the team is actively working to resolve the issues and prevent future occurrences.
Validation Bug Causes Transaction Acceptance Issues
On Saturday, a validation bug in a shared software library led to inconsistent transaction acceptance across different node versions. While some operators running the latest software accepted the malformed transaction, others with older versions rejected it, resulting in two competing chains.
Response from Intersect and Impact on Exchanges
Intersect, the governance body of Cardano's ecosystem, confirmed that the issue was quickly contained. However, as a precautionary measure, several exchanges and wallet providers temporarily halted deposits and withdrawals. Fortunately, the incident did not result in any loss of user funds, and most retail wallets remained unaffected.
Emergency Patch Issued for Network Stability
In response to the chain split, a network-wide emergency patch was promptly issued. Stake pool operators were urged to upgrade their software immediately to ensure they could reconnect to the correct chain and maintain network stability.
On November 21, 2025, the Cardano blockchain encountered a critical challenge due to a malformed transaction that led to a temporary network split, raising concerns about security and governance. For more details, see the full report here.
