Firo Rushes Urgent Hard Fork to Patch Critical Privacy Flaw

Node operators and wallet users rushing to update their software face a strict deadline as privacy coin Firo prepares for an essential network upgrade. The hard fork is scheduled to activate at block 1,371,000, bringing a permanent fix for a security vulnerability discovered in August within the Spark transaction system. Developers warn that nodes failing to upgrade before the threshold will become incompatible with the rest of the network.

The underlying bug, disclosed in mid August, involved multi input Spark spends and could have allowed unauthorized token creation under specific conditions. A security researcher successfully generated about 200 FIRO during a controlled test to demonstrate the issue, though the project team found no evidence of wider exploitation. While user wallets and private keys remained safe, the flaw posed a direct threat to the overall supply integrity of the asset.

As a temporary defense, an earlier software patch restricted Spark spending to single inputs, which protected the token supply while slightly weakening user privacy. The new version 0.14.18.0 update introduces a new transaction format that safely restores normal multi input spending without requiring users to migrate funds or change addresses. The development team plans to publish a full technical post mortem shortly after the upgrade goes live.