Zcash founder warns Orchard flaw may have enabled undetectable counterfeit ZEC

Zcash founder Zooko Wilcox said security researcher Taylor Hornby identified a critical counterfeiting vulnerability in Zcash's Orchard pool on May 29. Zcash Open Development Lab coordinated an emergency response that concluded on June 2. Shielded Labs said the issue was genuine and exploitable, adding that a local proof-of-concept could mint unlimited counterfeit ZEC that would be undetectable. Because Orchard is designed for privacy, the network cannot cryptographically prove whether the bug was abused before the fix. Shielded Labs said it considers prior exploitation unlikely. Shielded Labs is evaluating a potential network upgrade aimed at verifying the integrity of Zcash's supply and demonstrating the absence of counterfeit ZEC within the Orchard pool. At the time of writing, ZEC was trading at $443.05, down 29.0% over the past 24 hours.