Key facts
- A proposed fix uses one-time viewing keys for published addresses to prevent quantum computer attacks.
- The solution addresses risks from cross-chain swaps that post shielded Zcash addresses on public chains.
- No network upgrade is required for the proposed fix.
- Wallets like Vizor will integrate the feature in the coming weeks.
Zcash developer Zakura has proposed a new method to protect shielded Zcash payments from future quantum computers. The fix, detailed in an engineering post by developer Adam Tucker, aims to prevent a quantum computer from linking a user's private Zcash transactions by deriving a separate incoming viewing key for each published address. This approach does not require a network upgrade. The primary risk identified is from cross-chain swaps, such as those using NEAR Intents, where shielded addresses are posted on public blockchains. Around $600 million to $700 million had flowed through Zcash's NEAR Intents route by May. Wallets built on Zakura's open-source libraries, like Vizor, are expected to integrate the feature in the coming weeks, with hardware wallets to follow. Zcash is aiming for full post-quantum security within 12 to 18 months.