Zcash has patched a critical Orchard pool vulnerability after an AI-assisted security review found a flaw that could have allowed invalid activity inside the network’s newest shielded pool. T
Zcash has patched a critical Orchard pool vulnerability after an AI-assisted security review found a flaw that could have allowed invalid activity inside the network’s newest shielded pool.
The issue was discovered on May 29 by Taylor Hornby, an independent security researcher working on Zcash protocol research for Shielded Labs. The vulnerability affected the Orchard zero-knowledge proof circuit, a core part of Zcash’s shielded transaction system. Zcash developers confirmed the issue quickly, then moved through an emergency response that temporarily disabled Orchard actions before restoring normal operations through the NU6.2 network upgrade.
The fix did not stop the market reaction. ZEC fell roughly 35% intraday, sliding toward the $400 area as traders absorbed the difference between a patched bug and a deeper confidence problem around shielded supply verification.
The response moved in two steps. First, Zebra 4.5.3 implemented an emergency soft fork that temporarily disabled Orchard actions at mainnet block 3,363,426. That reduced the risk of exploitation while developers prepared the full circuit fix.
Then Zebra 5.0.0 activated NU6.2 at mainnet block 3,364,600 on June 3, restoring Orchard with a corrected circuit. Zcash Foundation said there was no evidence of unauthorized value creation, no known exploitation, no impact to user privacy, and no break in the total ZEC supply cap.
That is the clean operational side of the story. The bug was found, disclosed, confirmed and patched in days. Sapling and transparent Zcash transactions continued operating during the incident, while Orchard was paused for roughly 24 hours during the upgrade window.
The harder part is what Shielded Labs disclosed afterward.
A follow-up post by Zooko Wilcox, Jason McGee and Taylor Hornby described the flaw as a critical counterfeiting vulnerability in the Orchard pool. The post said Hornby used Anthropic’s Opus 4.8 as part of a targeted review of the Orchard circuit, alongside traditional security research methods.
The follow-up also said Hornby wrote a complete exploit in a local regtest environment that generated unlimited counterfeit ZEC inside Orchard. It did not say the exploit was used on mainnet. Shielded Labs said prior exploitation appears unlikely, but because Orchard is private by design, there is no way to cryptographically prove from Orchard alone whether the vulnerability was exploited before it was fixed.
That distinction is now driving the market response. Zcash’s turnstile mechanism can confirm the broader supply cap across value pools, and Zcash Foundation said no unauthorized value creation was detected. However, the privacy properties that make Orchard valuable also make historical proof harder inside the pool itself.
For a privacy coin, that is a serious narrative hit. ZEC’s investment case depends on both privacy and monetary confidence. If the market starts questioning whether shielded supply can be proven after a circuit flaw, price can move far faster than the technical fix.
Arthur Hayes turned that concern into a trade. In a new post, Hayes said the “Holy Trinity” is dead and that he sold his entire ZEC position after reviewing the Orchard issue. He said prior minting was “extremely unlikely,” but argued that a privacy asset built for protection from AI, governments and big-tech surveillance needs perfection rather than probability.
CryptoAdventure covered that reversal after Hayes said he sold his ZEC bag and removed Zcash from the privacy pillar of his earlier trade. That matters because Hayes had recently grouped ZEC with HYPE and NEAR in his crypto “Holy Trinity,” giving the token a strong narrative boost before the Orchard issue hit.
The market is now pricing both sides at once. The technical response was fast and coordinated. The confidence damage is still open.
Shielded Labs is exploring a future network upgrade that would let users verify the integrity of Zcash supply by moving into a new shielded pool and applying turnstile accounting to Orchard exits. That proposal would need community support and normal governance before activation, but it directly addresses the market’s biggest concern.
Zcash already showed that its developer ecosystem can react quickly under pressure. The next phase is different. The chain now needs a stronger public path toward supply assurance that does not weaken the privacy properties users came for in the first place.
ZEC’s drop shows the market is no longer only asking whether Orchard works again. It is asking whether Zcash can prove, in a way users and investors can trust, that privacy and monetary integrity can survive the same AI-assisted security era that exposed the flaw.
The post Zcash Patches AI-Assisted Orchard Flaw As ZEC Dumps 35% And Hayes Exits appeared first on Crypto Adventure.
