Zano rolls back blockchain by one month after exploit

Following a critical exploit in its Gateway Addresses feature, the privacy-focused Zano blockchain rolled back approximately one month of transaction history on September 27, 2026. The rollback, which restarted the chain at block 3,833,000, was executed to eliminate unauthorized ZANO and Freedom Dollar (fUSD) tokens. While the move successfully restored the fixed supply, it invalidated a month of legitimate transactions and triggered a 20% drop in the price of ZANO.

Implementation and impact of the rollback

• ▪The Zano blockchain rollback after the Gateway Addresses exploit requires participating nodes, miners, stakers, exchanges, and other services to adopt a coordinated network update
• ▪The Zano blockchain rollback executed on September 27, 2026 invalidates a month of legitimate transactions and cannot reverse payments already settled on other blockchains
• ▪The Zano core team stated it is working to account for transaction losses caused by the Gateway Addresses exploit and will publish a reimbursement and claims process
• ▪On September 27, 2026, the Zano core team restarted its blockchain at block 3,833,000, rolling back approximately one month of transaction history

The Gateway Address feature and vulnerability

• ▪The Zano core team identified a vulnerability in public Gateway Addresses, a feature designed to simplify integration for exchanges, bridges, and payment gateways
• ▪Zano launched Gateway Addresses on August 26, 2026, with Hard Fork 6 at block 3,833,000, using an on-chain account-based model instead of Zano's traditional UTXO system

Scope and impact of the exploit

• ▪Zano head of marketing Quinten van Welzen stated that doing nothing would have allowed unlimited unauthorized ZANO and fUSD in circulation, diluting holders
• ▪The Gateway Address vulnerability identified on September 25, 2026 allowed attackers to mint unauthorized ZANO and Freedom Dollar (fUSD) stablecoins, inflating the asset supply
• ▪The Zano core team confirmed that transaction privacy was unaffected by the Gateway Address vulnerability identified on September 25, 2026 and no user wallets or spend keys were compromised

ZANO price reaction

• ▪ZANO closed at $7.50 on September 24, 2026, after trading above $8.00 a few days prior, according to CoinGecko data
• ▪The price of ZANO dropped approximately 20% after the Gateway Addresses asset issuance vulnerability was reported on September 25, 2026

Wider cryptocurrency security context

• ▪Similar asset-creation exploits to the Zano Gateway Addresses exploit occurred in 2026 on the Liquid Network and involving Fetch.ai and NuNet, resulting in significant token value drops
• ▪TRM Labs recorded 207 cryptocurrency hacks in the first half of 2026, with infrastructure and operational problems accounting for 76% of total losses

Debatable claims

• ▪The Zano core team bears primary responsibility for the transaction losses caused by the rollback
• ▪Zano's one-month blockchain rollback was justified to preserve its token supply
• ▪Zano's adoption of an account-based model to simplify exchange integration was a mistake
• ▪Zano should fully compensate users for legitimate transactions invalidated by the rollback