Zcash (ZEC) has rebounded by 45% to $437 after developers proposed the Ironwood upgrade to address a critical flaw. The cryptocurrency had previously dropped due to a counterfeiting bug in its Orchard pool, which could have allowed unlimited fake ZEC creation. The bug was swiftly patched by Shielded Labs and other developers through emergency upgrades. The proposed Ironwood upgrade aims to restore confidence by creating a new privacy pool and preventing new coin creation in the compromised Orchard pool. This would enable users to verify the total ZEC supply independently. The proposal has garnered attention, with investor Chamath Palihapitiya highlighting its potential to ensure supply integrity. Developers have not specified a timeline for the upgrade's implementation.