Cardano Network Split by Attack on Hoskinson’s Stake Pool

On November 21, 2025, the Cardano network faced unprecedented disruption when a corrupted transaction targeting founder Charles Hoskinson’s personal stake pool triggered a chain split that lasted several hours. The incident began when a stake pool operator followed unverified AI-generated instructions to create a malformed transaction that exploited an obscure 2022 cryptographic library bug. This technical vulnerability caused newer Cardano nodes to parse the transaction incorrectly while older nodes rejected it outright, creating a fundamental incompatibility that fractured the network.

The chain split immediately disrupted block production across the Cardano ecosystem, leaving validators, DeFi protocols, and everyday users struggling to maintain synchronization. While user funds remained secure throughout the incident, the disruption had tangible financial consequences. Many stake pool operators lost block rewards during the hours of instability, and several decentralized applications experienced inconsistent states that required immediate developer intervention. The event demonstrated how a single misstep could cascade into a system-wide disturbance affecting the entire ADA cryptocurrency ecosystem.

The stake pool operator responsible for the incident later admitted to poor judgment, describing his actions as a personal challenge handled recklessly. In his public message, he insisted he had no financial motives, no collaborators, and no intention to specifically target Charles Hoskinson. He expressed regret for the disruption caused to fellow stake pool operators and developers who were forced to react immediately to stabilize the network. According to his account, the entire situation resulted from following unverified AI-generated instructions without proper testing or consideration of consequences.

Cardano founder Charles Hoskinson vehemently rejected this explanation, stating that the incident was anything but accidental. Hoskinson revealed that the individual responsible had been active in online communities known for hostility toward Cardano and its leadership. According to the founder, the attacker had spent months discussing ways to disrupt the project’s operations and reputation, with his personal stake pool serving as the direct target. Hoskinson emphasized that the disruption affected every user on the network, causing financial losses for operators and forcing emergency responses from developers.

The conflicting accounts have left the Cardano community divided between two competing narratives. One camp views the incident as a case of reckless experimentation by an individual operator, while the other sees it as calculated sabotage with malicious intent. This division highlights the challenge of establishing motive in blockchain security incidents where technical actions can have ambiguous intentions but clear consequences.

The Cardano incident exposed critical vulnerabilities in how blockchain networks handle edge cases and obscure bugs. The fact that a single malformed transaction could trigger hours of network disruption demonstrates the fragility that can exist even in established cryptocurrency platforms. The 2022 cryptographic library bug that was exploited had remained dormant for years, suggesting that similar vulnerabilities might exist undetected in other parts of the Cardano codebase and potentially in other blockchain systems.

Hoskinson’s revelation that law enforcement had become involved transforms the incident from a technical mishap to a potential criminal matter. This development signals increasing regulatory scrutiny of blockchain security incidents and establishes a precedent for how similar events might be handled in the future. The involvement of federal authorities also raises questions about liability and accountability in decentralized systems where traditional governance structures often struggle to apply.

For the broader cryptocurrency industry, the Cardano chain split serves as a stark reminder that network security extends beyond protecting user funds to maintaining consensus and operational stability. The incident demonstrates how targeted actions against specific network participants can have system-wide consequences, potentially creating new attack vectors that malicious actors might exploit. As blockchain networks like Cardano continue to evolve and integrate with DeFi protocols and other financial applications, ensuring resilience against such disruptions becomes increasingly critical for mainstream adoption and institutional confidence.