github.com
https://github.com/ZcashFoundation/zebra CVE-2026-40880
HIGH
Zebra: Cached Mempool Verification Bypasses Consensus Rules for Ahead-of-Tip Blocks
Record summary
CVE-2026-40880 has a selected CVSS score of 7.2 (high).
Description
ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.1 and zebra-consensus version 5.0.2, a logic error in Zebra's transaction verification cache could allow a malicious miner to induce a consensus split. By carefully submitting a transaction that is valid for height H+1 but invalid for H+2 and then mining that transaction in a block at height H+2, 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 vulnerability is fixed in zebrad version 4.3.1 and zebra-consensus version 5.0.2.
Description source: CVE List
Exploitation context
CISA SSVC decision
ExploitationNone
AutomatableNo
Technical impactPartial
CISA Coordinator · SSVC 2.0.3 · Evaluated Apr 21, 2026 · Source: CVE List
Affected products and versions
4| Product | Source | Version range | Status |
|---|---|---|---|
zebra-consensusBrowse ZcashFoundation / zebra-consensus | CVE List | < 5.0.2 | affected |
| CVE List | < 4.3.1 | affected | |
zebra-consensusBrowse crates.io / zebra-consensus | GitHub Advisory | Before 5.0.2 · Fixed in 5.0.2 | affected |
| GitHub Advisory | Before 4.3.1 · Fixed in 4.3.1 | affected |
References
3github.comConfirmation
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-xvj8-ph7x-65gf nvd.nist.gov
https://nvd.nist.gov/vuln/detail/CVE-2026-40880