CVE-2026-34377

Description

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.0 and zebra-consensus version 5.0.1, a logic error in Zebra's transaction verification cache could allow a malicious miner to induce a consensus split. By matching a valid transaction's txid while providing invalid authorization data, a miner could cause vulnerable Zebra nodes to accept an invalid block, leading to a consensus split from the rest of the Zcash network. This would not allow invalid transactions to be accepted but could result in a consensus split between vulnerable Zebra nodes and invulnerable Zebra and Zcashd nodes. This issue has been patched in zebrad version 4.3.0 and zebra-consensus version 5.0.1.

References

• https://github.com/ZcashFoundation/zebra/releases/tag/v4.3.0
• https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-3vmh-33xr-9cqh
• https://zfnd.org/zebra-4-3-0-critical-security-fixes-zip-235-support-and-performance-improvements