When Eli Ben-Sasson helped create the Zcash cryptocurrency nearly a decade ago, the cryptographer worried about human adversaries. He didn’t expect that machine intelligence would one day expose a flaw that had eluded years of expert human judgment.
That reality rattled investors recently after a security researcher working with Zcash used Anthropic’s Claude Opus 4.8 to uncover a critical vulnerability that had gone undetected for more than four years. After Zcash disclosed the flaw on June 4, the token — which traded at far higher levels just weeks earlier — tumbled about 50% as traders reassessed the security of one of crypto’s most prominent privacy networks.
The exploit struck at the heart of Zcash’s value proposition. The cryptocurrency relies on advanced cryptography to enable users to shield transaction details from public view, and investors have long viewed that mathematical foundation as one of the network’s defining strengths. The discovery that a flaw capable of creating an unlimited supply of tokens had gone undetected for years raised fresh questions about how artificial intelligence could reshape the race between those securing crypto networks and those trying to hack them.