Zcash has officially set July 28 as the activation date for its Ironwood network upgrade, a critical protocol change designed to replace the Orchard shielded pool after the revelation of an "infinity" counterfeiting bug. Core developer Sean Bowe announced that the upgrade will go live at block height 3,428,143, expected around 8 a.m. EST, confirming a one-week delay from the initially planned July 21 rollout to accommodate exchange, wallet, and mining pool preparations.
The Ironwood upgrade was proposed after developers disclosed the vulnerability in May 2026, which could theoretically allow an attacker to create unlimited counterfeit ZEC within the Orchard pool — Zcash’s primary privacy transaction system. Although Shielded Labs stated no evidence of exploitation had been found, emergency updates first disabled Orchard transactions, followed by a June 3 hard fork (NU6.2) to patch the underlying issue. With Ironwood, the existing Orchard pool will cease activity, and users must migrate funds through an accounting checkpoint into a newly created shielded pool. This process could reveal whether any counterfeit coins were ever minted, as any hypothetical counterfeiter would be forced to move their fake ZEC and risk exposure, or leave them irreversibly stranded.
Following the bug disclosure on June 3, ZEC plunged roughly 50% from $602.68 to $299.25, but has since recovered to around $492.61. Futures open interest surged 18% to $914.91 million in 24 hours after the activation announcement, with a positive funding rate of 0.0105%, signaling strong long-side demand. Analyst Vishal Dixit noted ZEC is trading above its 50-day and 200-day EMAs, with the 78.6% Fibonacci retracement level at $520 as the next key resistance. Separately, Zcash passed a supply milestone this week, with more than 80% of its maximum 21 million coins now issued.
