Zcash's value plummeted by nearly 38% following the revelation of a critical vulnerability that could have enabled undetectable counterfeiting.
Overview
- Zcash's value plummeted after the discovery of a serious flaw in its Orchard shielded pool.
- The vulnerability, found using AI-assisted auditing tools, could have allowed for the creation of unlimited counterfeit ZEC.
- Critics highlight that privacy coins carry unique risks, potentially leaving such vulnerabilities unnoticed.
Zcash's price took a steep nosedive after a significant vulnerability in its Orchard shielded pool was disclosed. This flaw, which had existed for over four years, raised alarms as it could have allowed undetectable counterfeiting.
According to CoinGecko, Zcash's price fell dramatically from $635 on Wednesday to a low of $309 on Thursday, before a minor recovery brought it back to around $330, reflecting a staggering decline of 37.8% within a single day.
https://t.co/v7BiOdzU9E
— zooko🛡🦓🦓🦓 ⓩ (@zooko) June 4, 2026
The flaw was identified on May 29 by security expert Taylor Hornby, using advanced AI tools. It stemmed from two lines of code within the Orchard circuit that manages Zcash's shielded transactions, which could allow a malicious actor to produce counterfeit ZEC without detection. If exploited before its revelation, it would have been impossible to prove any wrongdoing.
Shielded Labs, the organization overseeing Zcash's development, confirmed that the vulnerability persisted from the Orchard's activation in May 2022 until it was patched on June 1, 2026. They noted that due to the privacy features of Orchard, it is challenging to ascertain if any exploitation had occurred.
This alarming situation has reignited debates about inherent issues with privacy coins. Unlike Bitcoin and Ethereum, which permit immediate detection of on-chain exploits, privacy coins like Zcash may enable successful attacks to go unnoticed.
Crypto analyst Udi Wertheimer pointed out that Zcash creates a unique risk profile, suggesting that undetected bugs could pose a significant threat. "The specific bug being addressed does not eliminate the underlying risk," he emphasized.
Joe Andrews, CEO of Aztec Labs, remarked that the vulnerability's roots in elliptic curve checks are common in production ZK circuits, indicating that AI is accelerating the discovery of such flaws across the industry. He advocated for a comprehensive solution that includes formal verification of circuits alongside a secondary proof system, similar to Ethereum's approach.
Market Response Mixed
In the wake of the news, Arthur Hayes, former CEO of BitMEX, disclosed that he sold all his Zcash holdings. Investors are particularly concerned about the potential insolvency of the Orchard pool, which could dilute the holdings of legitimate shielded ZEC holders in the event of counterfeit claims.
The Holy Trinity is dead. Sadly due to the Orchard Pool exploit, I had to dump our entire $ZEC bag.
- While I think it's extremely unlikely of any minting, it cannot be formally cryptographically proved impossible
- The privacy from AI, govt, big tech narrative demands perfection…
— Arthur Hayes (@CryptoHayes) June 5, 2026
On the other hand, Craig Salm, Grayscale's chief legal officer, expressed skepticism regarding the likelihood of the vulnerability being exploited before the patch was applied. He argued that exploiting the flaw would require a level of scrutiny beyond that of all core developers combined, making it seem unlikely.
In light of these developments, Shielded Labs has proposed a network upgrade to introduce a new shielded pool with turnstile accounting to ensure the integrity of the Zcash supply. This new design would require all coins to be unshielded before entering the new pool, thereby limiting the risks from any prior exploitation to the current amount of shielded assets. Andrews noted that formal verification of this upgrade would further mitigate risks significantly.
