CVE-2026-34377
Zebra has a Consensus Failure due to Improper Verification of V5 Transactions
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| rust | zebrad | < 4.3.0 | 4.3.0 |
| rust | zebra-consensus | < 5.0.1 | 5.0.1 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Zfnd | Zebra | before 4.3.0 |
| Zfnd | Zebra-Consensus | before 5.0.1 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-3vmh-33xr-9cqh
- 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
- https://zips.z.cash/zip-0244
- https://nvd.nist.gov/vuln/detail/CVE-2026-34377
- https://github.com/ZcashFoundation/zebra/releases/tag/v4.3.0