Crypto
Home›Crypto›Market Structure›Zcash activates Ironwood upgrade, sealing Orchard shie…
Zcash activates Ironwood upgrade, sealing Orchard shielded pool
The Ironwood (NU6.3) upgrade was activated at block 3,428,143, moving funds from a roughly 3.66 million ZEC Orchard pool into a new private pool that starts with zero ZEC.
CoinDesk reports that Zcash has activated its Ironwood (NU6.3) upgrade, sealing the Orchard shielded pool and opening a new private pool that begins with zero ZEC. The update is designed to replace the prior Orchard pool after research identified a serious issue in its proof circuit.
According to CoinDesk, Orchard held about 3.66 million ZEC, valued at roughly $1.7 billion at current prices, and Ironwood shows zero ZEC at activation. Every coin must be migrated by its owner, and Orchard’s only exit is a turnstile mechanism that caps total withdrawals to amounts verifiably deposited, using zero-knowledge proofs to connect private deposits to public evidence.
The upgrade follows the May 29 finding by Shielded Labs researcher Taylor Hornby that Orchard’s proof circuit contained a bug that could have enabled an attacker to mint counterfeit ZEC without leaving on chain traces. CoinDesk reports that the flaw was live since Orchard launched in May 2022, though evidence reviewed by CoinDesk Research suggested no exploitation, including because Orchard balances grew steadily through the period when selling counterfeit coins would have been most profitable.
CoinDesk adds that while developers patched the bug within days, the patch could not retroactively address the four years the vulnerability was open. Ironwood also introduces quantum-resilient record keeping and formally verified proof circuits, with the speed of user migration expected to determine how quickly Zcash’s private supply shifts to the new pool.