Zano Hits Undo on Itself, Rolls Back a Month After Exploit Lets Extra Tokens Slip In 🪙

Zano has rolled back approximately one month of blockchain history following a vulnerability in its Gateway Addresses feature that allowed unauthorized ZANO and Freedom Dollar to enter circulation, the project's core team announced Sunday. The chain has been restarted at block 3,833,000, the point immediately before Hard Fork 6 introduced the affected functionality. The recovery depends on nodes, miners, stakers, exchanges and other services adopting the update.

The rollback invalidates roughly a month of legitimate transactions alongside the unauthorized tokens, meaning activity recorded during that window will no longer appear on the recovered chain. It also cannot reverse payments already settled on external blockchains, and the team said a reimbursement and claims process will be published. No post-mortem has been released as of publication.

Gateway Addresses were built to simplify how bridges, exchanges and payment services integrate with Zano by letting them manage funds through a single account-style balance, replacing the chain's prior UTXO-based wallet model in which exchanges had to scan the blockchain, track outputs and select which ones to spend when processing withdrawals. The exploit exploited that new layer to mint tokens beyond the project's stated supply.

"Doing nothing meant unauthorized ZANO and fUSD in circulation without limit, diluting every holder and breaking the most basic promise a currency makes: a fixed supply," said Quinten van Welzen, Zano's head of marketing and growth. "It would also tell every future attacker that exploited coins get to keep their value. No project survives that."

Zano launched in May 2019 as a layer-1 blockchain focused on private payments, with standard transactions concealing senders, receivers, transferred amounts and asset types. Beyond its native ZANO token, the network supports custom digital assets, including the fUSD stablecoin issued on Zano. The chain's block explorer confirms the rollback took place Sunday at the specified block height.

"Restarting the chain from before Hard Fork 6 costs a month of history, and it costs trust, which we'll have to earn back," van Welzen added. "But it restores the supply everyone signed up for, and it leaves a path to rebuild. Which is better than 7 years of hard work left to die. We know it hurts. But not doing it would have hurt more."