SKN | Zano Rolls Back One Month of Blockchain History After Gateway Address Exploit

Key Takeaways

• Zano restarted its blockchain at block 3,833,000, effectively removing roughly one month of transaction history after a Gateway Address vulnerability enabled unauthorized ZANO and fUSD issuance.
• The exploit did not compromise wallet spend keys or ordinary transaction privacy, but it created a direct threat to the network’s monetary supply and transaction integrity.
• ZANO fell sharply during the incident, with its price closing at $6.48 on Sept. 27 after trading as high as $8.29 the previous day, highlighting the market’s sensitivity to protocol-level security failures.

Zano has executed an unusually extensive blockchain rollback after discovering a vulnerability in its newly introduced Gateway Address system. The emergency recovery comes as crypto investors increasingly evaluate not only token economics and liquidity, but also whether blockchain infrastructure can preserve transaction integrity when critical vulnerabilities emerge.

Zano Reverts to Pre-Hard Fork 6 State

The network was restarted at block 3,833,000, the point immediately before Hard Fork 6 activated on Aug. 26. Gateway Addresses were introduced through that upgrade to simplify integrations for exchanges, bridges, decentralized exchanges and payment services by providing an account-style balance mechanism.

The vulnerability allowed unauthorized ZANO and Freedom Dollar, or fUSD, to enter circulation. Rather than allowing potentially unbounded unauthorized supply to remain on the network, the project chose to invalidate approximately one month of subsequent blockchain history.

The decision carries a significant trade-off. Transactions confirmed during the affected period are no longer part of the recovered chain, meaning legitimate users and businesses must reconcile payments and maintain transaction records. Payments already settled on other blockchains cannot be reversed through the rollback.

ZANO Price Shows Immediate Security Impact

Market data illustrates the pressure created by the incident. ZANO closed Sept. 24 near $7.60 before falling to $5.95 on Sept. 25, a decline of about 21.7%. It recovered to $6.81 on Sept. 26 before closing at $6.48 on Sept. 27.

Trading activity also became highly elevated. ZANO volume reached roughly 1.90 million units on Sept. 25, compared with about 1.58 million on Sept. 24 and just 633,000 on Sept. 26. The sharp increase indicates substantial repositioning as traders assessed the consequences of the exploit and subsequent network recovery.

By comparison, the broader market remained significantly larger and more resilient. Bitcoin traded around $83,476 on Sept. 28, while Ethereum was near $2,658, with global crypto market capitalization around $2.94 trillion.

Rollback Tests Blockchain Finality and Trust

The most important issue extends beyond ZANO’s price. A month-long rollback demonstrates the difficult balance between fixed monetary supply, transaction finality and emergency governance. Zano said its core consensus mechanism and ordinary transaction privacy were not compromised, narrowing the vulnerability to the Gateway Address functionality.

The recovery nevertheless requires nodes, miners, stakers, exchanges and other service providers to adopt updated software. The project is also preparing a reimbursement and claims process for affected users and counterparties.

Recovery Will Depend on Transparency and Infrastructure Rebuild

Zano’s next stage will depend on the technical post-mortem, reconciliation of legitimate transactions and the restoration of third-party services. For professional crypto participants, the incident reinforces the importance of evaluating upgrade risk and operational dependencies alongside token liquidity and protocol design. The effectiveness of the recovery process will determine whether Zano can rebuild confidence while demonstrating that the Gateway Address architecture has been sufficiently reviewed before similar functionality returns to production.