Zcash fell by 50% after a four‑year‑old secret emerged, and a quiet recovery is already underway.
A security researcher discovered a critical, four-year-old flaw in Zcash's Orchard shielded pool. The vulnerability was a "soundness" issue that theoretically allowed the creation of undetectable counterfeit ZEC. Although the flaw did not inflate the total supply, the inherent privacy design made confirming exploitation impossible. This discovery caused immense market uncertainty and triggered a steep price decline for ZEC. The development ecosystem quickly executed a rapid, two-phase emergency upgrade. The first phase temporarily paused all Orchard transactions to isolate the attack path. The second phase deployed a hard fork, introducing a corrected circuit and a new key to successfully patch the vulnerability. This swift response was critical for maintaining network stability and securing the core protocol. The initial vulnerability disclosure led to a significant crash in the asset's price. Subsequent positive signals, including the successful patch deployment, fueled the recovery. The Foundation's transparency and confirmation that the network passed without confirmed exploitation restored market confidence. The cleanup of this core privacy flaw marks a pivotal moment for Zcash's long-term value proposition.