Zano Reverts Approximately One Block Following Gateway Address Vulnerability

Zano Rolls Back About One Month of Chain History After Gateway Address Vulnerability

Zano, a privacy-focused blockchain, restarted its chain from block height 3,833,000 after a Gateway Address vulnerability allowed unauthorized ZANO and fUSD to enter circulation. The restart point is earlier than the August 26 activation of Hard Fork 6, effectively rolling back about one month of on-chain history.

What the rollback means

Transactions confirmed during the affected period will not be part of the restored main chain. Users and services that relied on those confirmations may need to reassess balances and transaction records once the network is rebuilt.

Security scope and recovery plan

Zano said wallet spending keys, ordinary transaction privacy and core consensus were not affected. The team is calculating losses with affected projects and counterparties and plans to publish compensation and claims procedures.

Risk Disclaimer

This article is an information summary only and does not constitute investment advice. Crypto assets, including privacy tokens and stablecoins, are highly volatile and may be affected by chain rollbacks, vulnerabilities, and network changes. Past confirmations or balances may become disputed. Readers should verify official announcements, assess risks independently, and avoid decisions based solely on this content.

Background: privacy chains and gateway addresses

In privacy-focused blockchain networks, the main design goal is usually to make transaction data harder to trace or publicly interpret than on fully transparent chains. That can include hiding transfer details while still allowing participants to verify validity through cryptographic rules. When assets move between different systems, gateways, bridges, or account abstractions may be used to connect on-chain states with external accounting flows. If such an interface is flawed, assets that should only exist under controlled conditions may appear outside those controls.

Interpretation: why roll back rather than patch only

A rollback is a disruptive but sometimes practical response when the integrity of the public state can no longer be trusted. If unauthorized tokens or balances have already been used, simply disabling the vulnerable address may not restore the original accounting position. Restarting from an earlier height can remove the disputed history and create a cleaner baseline for recovery.

Because the restart point is described as earlier than the activation of Hard Fork 6, the restored chain is expected to exclude the state and transaction history that accumulated after that earlier point. This can have practical consequences for applications, wallets, and services that had processed confirmations during the affected period. Their records may no longer match the canonical chain, so reconciliation becomes necessary before trust can be rebuilt.

Zano and ZANO background

Zano is described in the source material as a privacy-focused blockchain, while ZANO and fUSD are the assets mentioned as entering circulation through the vulnerable Gateway Address. In systems that combine a native token with a stablecoin-like unit, interface-level controls matter as much as base-layer consensus, because value can move through accounts, applications, and counterparties rather than through direct user transfers alone.

Key points

The reported issue points to a state-integrity problem rather than a direct theft of spending keys. The rollback aims to restore a pre-disputed baseline, but it also invalidates confirmations made during the affected period. Loss assessment and claims procedures will therefore be central to whether users, projects, and counterparties can reconcile balances and rebuild confidence.