Back
Anthropic’s Zcash audit finds no serious bugs, boosting confidence

Anthropic’s Zcash audit finds no serious bugs, boosting confidence

A fresh Mythos review commissioned by Shielded Labs adds support for Zcash after the Orchard flaw, as developers pursue broader changes including the proposed Ironwood shielded pool.

ZEC

Fact Check
The originating primary source, Zooko Wilcox's own X post (@zooko), states word-for-word that at Shielded Labs's request Anthropic ran a Zcash security audit with Mythos, found no more serious bugs in the protocol, and that hardening work continues. This is directly corroborated by CryptoBriefing and two independent crypto outlets (BlockBeats and Odaily), both citing the same original tweet. Every element of the claim — the actor (Anthropic), the tool (Mythos), the requester (Shielded Labs), the outcome (no additional serious vulnerabilities), and ongoing hardening — matches the primary statement.
Summary

Anthropic’s Mythos tool found no additional serious vulnerabilities in Zcash, giving the privacy-focused network a fresh security endorsement after a critical Orchard shielded pool bug triggered a sharp selloff earlier in June. Zcash founder Zooko Wilcox-O’Hearn said the audit was commissioned by Shielded Labs, with prompts developed by Defuse Security, and thanked Anthropic as broader hardening work continues. The finding follows the disclosure of a four-year-old flaw discovered by Taylor Hornby that could have allowed unlimited counterfeit ZEC, though Zcash developers said there was no evidence of exploitation. ZEC fell about 53% from roughly $621 to $303 on June 5 after the disclosure, later rebounded to $427.67 on June 8, and was trading around $415 at the time of publication with a market capitalization above $6.94 billion, according to CoinMarketCap. Zcash developers have also proposed Ironwood, a new shielded pool design that would use turnstile accounting to migrate legitimate coins out of Orchard and block any counterfeit coins from moving into the new pool.

Terms & Concepts
  • Orchard shielded pool: A Zcash pool for shielded transactions that was found to contain the flaw at the center of the recent security incident.
  • Ironwood: A proposed new Zcash shielded pool designed to replace Orchard with added safeguards including formal verification and independent audits.
  • turnstile accounting: A mechanism intended to move legitimate coins into a new pool while preventing any counterfeit coins from carrying over.