Zcash to Activate Ironwood Upgrade July 28, Retire Orchard

The Zcash network will activate a critical upgrade called Ironwood on July 28 to permanently address a vulnerability that could have allowed the creation of counterfeit tokens. The upgrade, set for block height 3,428,143 at approximately 8 a.m. EST, will retire the compromised Orchard shielded pool and create a new private transaction pool.

The vulnerability, an "infinity bug" within the Orchard privacy layer, was first disclosed in May. It represented a fundamental flaw that could have permitted unlimited counterfeit ZEC to be minted undetected, directly threatening the network's core economic assumptions. Emergency patches were applied in early June, including a soft fork to temporarily disable the pool, but Ironwood is the definitive fix.

Ironwood's most significant feature is its migration mechanism. The existing Orchard pool will be closed to new activity, and users must move their funds to the new pool through a public accounting checkpoint. This process is designed to act as a forensic test, forcing any hypothetical counterfeiter to either attempt to move fake tokens and risk exposure or abandon them. According to developers, this checkpoint will allow for real-time...