Researcher Adds Monero to Audit Queue; XMR Drops 10%

Taylor Hornby, the security researcher who used Anthropic’s Claude Opus 4.8 to find a critical flaw in Zcash’s Orchard shielded pool, confirmed he will add Monero to his audit queue. After the announcement, Monero’s XMR fell roughly 10% to $298.76.

Hornby was commissioned by nonprofit developer Shielded Labs in April. He ran a custom auditing agent paired with Opus 4.8 on May 29 and within a day flagged an under‑constrained elliptic curve check in Orchard. The flaw dated to Orchard’s May 2022 launch and could have allowed undetectable ZEC counterfeits inside the shielded pool. Engineers released a patch on June 2.

Shielded Labs stated that prior exploitation appears unlikely but cannot be ruled out cryptographically. The initial public disclosure coincided with sharp market moves: ZEC lost about 30% of value after the finding and later recovered roughly 20%, trading near $373.27 at the time of reporting.

Responding to requests to probe other privacy coins, Hornby posted, “Absolutely! I’ll add Monero to my queue of things to audit.” He added that other privacy projects are on his list, that he plans to apply for a Zcash coinholder grant to fund the work, and that voluntary donations are appreciated but not required.

Monero uses privacy by default, unlike Zcash’s optional shielded transactions. A recent Monero network upgrade introduced additional privacy features, which expands the sections of code Hornby plans to review. Market reaction to his announcement was immediate, with XMR trading around $298.76 at the time of reporting.

The Zcash discovery was one of the first high‑profile security issues found with the aid of Opus 4.8 after the model’s release. The incident prompted a push for formal verification and additional scrutiny of privacy‑focused protocols. A separate verification effort backed by the Winklevoss twins is underway to reduce the risk of similar flaws.

Engineers patched the Zcash defect within days of the report. Institutional holders of ZEC are reviewing exposure, and privacy‑coin developers are monitoring ongoing audits as Hornby expands his work.