"Privacy blockchain project Zano said it rolled back its blockchain to block height 3,833,000, before its sixth hard fork, and deleted about one month of on-chain transaction records to address an inflation bug involving Gateway Addresses. According to Odaily, the bug allowed unauthorized issuance of the native ZANO token and the dollar-pegged stablecoin fUSD.
Zano said its core consensus protocol, wallet spending keys, and ordinary transaction privacy were not affected. It added that nodes, miners, stakers, and service providers need to upgrade.
Freedom Dollar said millions of dollars in assets held by the project had been exchanged for fake fUSD, and that the project will bear the related losses. Freedom Dollar also asked fUSD holders to pause economic activity involving the token until the repaired Zano chain" means that Zano discovered a serious token-issuance flaw that may have allowed attackers to create ZANO and fUSD without authorization.
To contain the issue, Zano reverted its blockchain to an earlier point—block 3,833,000, before the sixth hard fork. In practical terms, this removed roughly a month of blockchain history after that point, so transactions recorded during that period may no longer be valid on the repaired chain.
The reported vulnerability was related to “Gateway Addresses,” rather than the fundamental privacy design of Zano. Zano says its consensus mechanism, users’ wallet spending keys, and normal transaction privacy were not compromised. However, infrastructure participants such as node operators, miners, stakers, and service providers need to upgrade their software so they follow the repaired chain.
Freedom Dollar, the issuer or operator associated with fUSD, says fraudulent fUSD was used to exchange for millions of dollars’ worth of its assets. It says it will absorb those losses, but holders should avoid transferring, trading, redeeming, or otherwise using fUSD until the updated Zano blockchain is confirmed stable. The main risk is uncertainty over which transactions and token balances remain valid after the rollback.
Zano said its core consensus protocol, wallet spending keys, and ordinary transaction privacy were not affected. It added that nodes, miners, stakers, and service providers need to upgrade.
Freedom Dollar said millions of dollars in assets held by the project had been exchanged for fake fUSD, and that the project will bear the related losses. Freedom Dollar also asked fUSD holders to pause economic activity involving the token until the repaired Zano chain" means that Zano discovered a serious token-issuance flaw that may have allowed attackers to create ZANO and fUSD without authorization.
To contain the issue, Zano reverted its blockchain to an earlier point—block 3,833,000, before the sixth hard fork. In practical terms, this removed roughly a month of blockchain history after that point, so transactions recorded during that period may no longer be valid on the repaired chain.
The reported vulnerability was related to “Gateway Addresses,” rather than the fundamental privacy design of Zano. Zano says its consensus mechanism, users’ wallet spending keys, and normal transaction privacy were not compromised. However, infrastructure participants such as node operators, miners, stakers, and service providers need to upgrade their software so they follow the repaired chain.
Freedom Dollar, the issuer or operator associated with fUSD, says fraudulent fUSD was used to exchange for millions of dollars’ worth of its assets. It says it will absorb those losses, but holders should avoid transferring, trading, redeeming, or otherwise using fUSD until the updated Zano blockchain is confirmed stable. The main risk is uncertainty over which transactions and token balances remain valid after the rollback.