Zcash founder Zooko Wilcox-O’Hearn publicly thanked Anthropic this week, confirming the artificial intelligence (AI) company ran a full security audit of the Zcash protocol using its restricted frontier model, Mythos, and found no additional critical vulnerabilities.
Key Takeaways:
Anthropic’s restricted Mythos AI audited the full Zcash protocol at Shielded Labs’s request and found no new critical bugs as of June 12, 2026.ZEC trades around $411 to $416 on June 13, recovering from June 5 lows near $300 after the Orchard circuit bug was patched via NU6.2.Shielded Labs and Zcash contributors continue security hardening work ahead of the Ironwood upgrade, targeting late July 2026.“Thanks, Anthropic, for helping protect Zcash users. At Shielded Labs’s request, they ran a security audit of Zcash with Mythos. It did not find any more serious bugs in the Zcash protocol. Shielded Labs and others are continuing security hardening work. Stay tuned for updates.”
The post arrived one week after the public disclosure of a critical soundness bug in the Orchard shielded pool, which had triggered a 38% to 50% price collapse in ZEC within 48 hours of going public on June 4 and 5.
What Mythos Is and Why It MattersShielded Labs, the nonprofit organization supporting Zcash development, secured access to Mythos and directed the audit at the entire Zcash protocol.
The Orchard Bug That Triggered the CrisisThe Mythos audit follows a harrowing episode for Zcash holders. In late May 2026, security researcher Taylor Hornby, working under contract with Shielded Labs, used a custom AI auditing framework built around Claude Opus 4.8 to identify an under-constrained circuit element in the Orchard shielded pool’s zero-knowledge proof system. The flaw had existed since Orchard’s activation in May 2022 and had gone undetected for approximately four years despite prior expert audits.
Developers moved fast. A soft fork on June 2 temporarily disabled all Orchard actions. A hard fork on June 3, the NU6.2 upgrade, activated a corrected circuit and re-enabled Orchard with no chain split.
What the Clean Audit Means for ZEC HoldersThe Mythos result does not close the book on security work. Zooko was explicit that efforts continue. Shielded Labs and other contributors are pressing forward with security hardening, which includes formal verification of the Orchard circuit, additional AI-assisted auditing, and plans to hire a Head of Security and a dedicated cryptographer.
ZEC Price Holds Above $400The Mythos audit result, combined with the speed of the emergency fix and the Ironwood roadmap, has supported the recovery. Price remains well below the June 4 peak near $624, with the next major catalyst likely tied to progress on Ironwood.
Security Work ContinuesZooko’s statement closed with a clear signal: this is not a declaration of completion. “Stay tuned for updates,” he wrote, pointing to an ongoing program that now includes some of the most advanced AI security tooling available anywhere.
For ZEC holders, the clean Mythos audit provides meaningful reassurance after a turbulent two weeks. The protocol’s most powerful available reviewer found nothing new. The team is still looking.
