Zano Rolls Back a Month of Blocks After Gateway Address Bug

Quick answer: Zano, a privacy-focused layer-1 blockchain, rolled its chain back to block 3,833,000 on September 28, 2026, wiping roughly a month of transaction history. The reason was a flaw in “Gateway Addresses,” a feature added in Hard Fork 6, which let unauthorized ZANO and fUSD (Freedom Dollar) tokens be created without limit. The team says wallet keys and transaction privacy weren’t compromised, that no new tokens will be minted to cover losses, and that Gateway Addresses stay offline until they’re reviewed and audited. The exact amount of illegitimate supply was not in the first reports. A later Crypto Economy report (October 2), citing a Zano team update we haven’t seen directly, puts it at about 36.9 million ZANO and roughly 1.8 quadrillion fUSD, while other outlets quote different figures, so treat the numbers as unconfirmed.

That’s the short version. The longer one is more interesting, because a rollback is one of the most uncomfortable tools a blockchain community can reach for. It works, but it trades away something crypto people care about a great deal: the idea that history is final.

What actually happened to Zano

Zano launched in May 2019 and positions itself as a layer-1 network built around private transactions. On August 26, 2026, Hard Fork 6 activated at block 3,833,000. Among other changes, it introduced Gateway Addresses, according to reporting from Cryptonomist and Crowdfund Insider.

Zano normally works on a UTXO-style model, similar in spirit to Bitcoin’s. Gateway Addresses were a deliberate departure. They give exchanges, bridges and payment providers account-style addresses with publicly queryable balances, which are far easier to integrate than shielded, output-based accounting. Convenience for integrators was the pitch.

Then came the flaw. Within a few weeks, the team found that the feature could be abused to bring ZANO and fUSD into existence that shouldn’t have existed. Crowdfund Insider reports the core team announced the vulnerability on September 25 and initially floated a rollback of about 24 hours. The plan that was ultimately carried out was far bigger: the network restarted from block 3,833,000, the block immediately before Hard Fork 6, which Cointelegraph, Blockonomi and Cryptonomist all describe as roughly a month of history.

One caution on dates. The September 25 announcement date comes from a single outlet, and the team’s own communications were spread across social channels. The September 28 restart is confirmed by several reports. Treat the earlier date as likely, not gospel.

Why a supply bug is more serious than it sounds

If you follow crypto security, you’re used to stories where an attacker steals funds. This is a different failure. Nothing needed to be stolen for the damage to happen. Unauthorized tokens entering circulation dilute every honest holder, because the same real economic activity is now spread across more units.

Quinten van Welzen, Zano’s head of marketing and growth, put it plainly in comments reported by Cointelegraph: doing nothing meant unauthorized ZANO and fUSD in circulation without limit, diluting every holder. For a stablecoin-like asset such as fUSD, the problem is sharper still. A dollar-pegged token only means something if every unit is backed. Counterfeit units undermine that for everyone holding the real ones.

That’s the same reason supply-integrity bugs tend to end in emergency responses rather than quiet patches. You can fix the code going forward, but you can’t easily tell which tokens in a wallet are legitimate. Rolling back sidesteps that question by deleting the period in which the bad tokens were created.

The rollback, step by step

Based on the reports, the sequence looked like this:

• August 26: Hard Fork 6 goes live at block 3,833,000, activating Gateway Addresses. Blockonomi notes at least two Gateway Addresses were created in the first seven days, each requiring a 100 ZANO registration fee.
• Around September 25: The core team discloses the supply vulnerability and asks users to pause economic activity while a fix is prepared (Crowdfund Insider).
• September 28: The network resets to block 3,833,000 using a coordinated release, reported as version 2.2.3.600. Standard wallet users can upgrade without re-entering recovery phrases.
• September 29: The team says the network is stable. Gateway Addresses remain disabled pending review and audit.

A coordinated reset like this needs buy-in from the people who run the network: node operators, mining and staking pools, and exchanges. Crowdfund Insider describes the plan as requiring majority consensus among those groups. That’s worth remembering when you hear people say rollbacks are “just a decision.” They’re a social process as much as a technical one.

What it costs holders

Here’s where it gets uncomfortable. A rollback that discards a month of history doesn’t only remove the bad tokens. It also removes every legitimate transaction made in that window. If you received a payment, swapped, or moved funds on the Zano chain during that month, that transaction no longer exists on the surviving chain.

The team’s stated approach to compensation, per Cryptonomist:

• No new tokens will be minted to make people whole.
• Funding will come from the development fund, team members’ personal holdings and committed contributors.
• Users don’t need to take action yet. Instructions will follow after verification.
• Assets that were converted into USDT or DAI on other networks fall outside the recovery scope.

That last point matters most in practice. Imagine you sold ZANO on an exchange during the affected window, withdrew the proceeds as USDT, and went about your week. The ZANO leg of that trade may no longer exist on-chain after the reset, while the USDT is real and sitting in your wallet. Who absorbs that mismatch depends on how the exchange handles it and on the claims process, which hasn’t been published in detail.

Market and exchange reaction

Price action was rough but not catastrophic. Cryptonomist reported ZANO down about 12.85% over 24 hours to roughly $6.32, with a market capitalization near $97.6 million. Crowdfund Insider, writing earlier in the process, said the token had fallen around 20% following the initial announcement. Those two numbers measure different windows, so they don’t contradict each other.

On the plumbing side, MEXC suspended ZANO and fUSD deposits and withdrawals during the migration. Other exchanges are updating individually, so rollout is uneven. If you hold Zano on any venue, check that venue’s status page before assuming deposits and withdrawals are back.

A reader scenario: what you’d do on Monday morning

Say you hold a modest ZANO position across a self-custody wallet and one exchange account. You wake up to the news. What’s the sensible order of operations?

First, don’t panic-transact. The team asked users to hold off on economic activity around the reset, and moving funds while nodes are on different chain versions is how people end up with transactions that vanish.

Second, update your wallet to the release the team points to through its official channels, not a link from a reply or a direct message. Reset events are prime time for fake “recovery” sites and phishing. If you want a refresher on spotting those, our guide on how to spot a crypto scam covers the patterns.

Third, write down any transfers you made during the affected month: dates, amounts, counterparties. If a claims process opens, that record is your evidence.

Finally, on the exchange side, wait for your platform to confirm it has completed its migration before you deposit or withdraw.

The bigger question: is a rollback compatible with “immutable”?

This is the debate underneath the headlines. Blockchains sell finality. When a network erases a month, some holders see a responsible emergency fix and others see proof that the chain’s history is only as permanent as its community’s willingness to leave it alone.

Both readings have merit. Zano’s team appears to have concluded that unlimited counterfeit supply was worse than a rewrite, and said as much: the rollback “costs trust, which we’ll have to earn back,” as Cointelegraph paraphrases the team’s position. That’s a candid admission, and it’s fair to give them credit for it.

But it does show a structural reality. A smaller network with a coordinated set of exchanges, pools and node operators can execute a reset that a large, widely distributed chain realistically couldn’t. Ethereum’s history around The DAO is the famous precedent, and it split the community. Zano’s market capitalization, around $97.6 million per the Cryptonomist figures, is tiny next to the majors, which is part of why coordination was feasible.

Lessons for anyone holding smaller-cap chains

This isn’t a story about one bad line of code. It’s a reminder of how new features on young networks carry risk that mature ones have largely shaken out.

• New features are the riskiest features. The flaw sat in code that had been live for about a month. Fresh hard forks deserve extra caution.
• Convenience features create attack surface. Account-style balances made integration easier and also opened a path the original design didn’t have.
• Supply integrity is a security category of its own. Watching for hacks isn’t enough. Inflation bugs can hurt you without any funds being taken.
• Your counterparty’s plan matters. How an exchange treats a rollback determines whether you’re made whole.

We’ve seen a related pattern in 2026’s record run of DeFi price-manipulation hacks, and in the governance-driven Term Finance exploit. Different mechanics, same lesson: code that touches value needs adversarial review before, not after, launch. The week’s much larger Bitget breach sits at the other end of the scale.

What to watch next

• Publication of the promised technical explanation and the claims process.
• Confirmation of the amount of unauthorized ZANO and fUSD from the team’s own channels. Reported figures differ between outlets.
• An independent audit before Gateway Addresses are switched back on.
• Exchange-by-exchange confirmation that deposits and withdrawals are running on the new chain.

Zano also sits in the privacy-coin corner of the market that has been drawing fresh attention this year, as we covered when Zcash’s spot ETF ignited the privacy-coin rally. Privacy chains get scrutinized harder than most, and an incident like this won’t help that.

FAQ

What is Zano?

Zano is a layer-1 blockchain launched in May 2019 that focuses on confidential transactions. It has its own native coin, ZANO, and a confidential stablecoin called Freedom Dollar (fUSD).

What went wrong?

A vulnerability in Gateway Addresses, introduced with Hard Fork 6 on August 26, 2026, allowed unauthorized ZANO and fUSD to be created. The team rolled the chain back to block 3,833,000 to remove them.

Were wallets or private keys compromised?

According to the team, no. Reports say spend keys, wallets and transaction privacy mechanisms were not affected.

How much unauthorized supply was created?

Early reports gave no figure. Crypto Economy later reported, citing a Zano team update, about 36.9 million ZANO and roughly 1.8 quadrillion fUSD, while another outlet cited 18.4 million ZANO and a $200 million value. We haven’t verified either against the team’s own post, so treat any specific figure as unconfirmed.

Do I need to do anything as a holder?

Upgrade to the release announced through Zano’s official channels and check your exchange’s status. The team says further instructions will follow after verification of the reimbursement process.

Will I be reimbursed if I lost money?

The team says it will work to account for losses using the development fund and team holdings, without minting new tokens. A formal claims procedure hadn’t been published in the reports we reviewed, and assets already converted to USDT or DAI on other networks are outside the stated scope.

Can this happen on Bitcoin or Ethereum?

A month-long reset would be extraordinarily hard on either, given how many independent participants would have to agree. That difficulty is, in a sense, what the finality promise looks like in practice.

Key Takeaways

• Zano reset its chain to block 3,833,000 on September 28, 2026, erasing about a month of history.
• The trigger was a Gateway Address flaw from Hard Fork 6 that allowed unauthorized ZANO and fUSD to enter circulation.
• The team says keys and privacy weren’t compromised; Gateway Addresses remain offline pending audit.
• Reimbursement will come from the development fund and team holdings, with no new minting. Details are still to come.
• The exact size of the unauthorized supply is still unconfirmed, with outlets reporting different figures.
• Rollbacks are feasible mainly on smaller, tightly coordinated networks, and they cost trust.

Sources & further reading

• Cointelegraph: Zano rolls blockchain back a month after Gateway Address exploit
• Cryptonomist: Zano Gateway vulnerability sparks network recovery effort
• Cryptonomist: Zano blockchain rollback halts unauthorized token minting
• Crowdfund Insider: Zano plans chain rollback after Gateway Address inflation bug
• Blockonomi: Zano network rewinds 30 days following Gateway Address security flaw
• Zano project website

Disclaimer: This article is for educational purposes only and is not financial advice. Crypto assets are volatile and smaller networks carry additional technical risk. Details of this incident were still developing at publication, so always do your own research (DYOR) and check official project channels.

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