Vulnerability in Zcashfoundation Zebra-Consensus
CVE-2026-40880
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.
EPSS: 0.003 (17.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.
Affected products
- Zcashfoundation Zebra-consensus — versions < 5.0.2
- Zcashfoundation Zebrad — versions < 4.3.1
- Zfnd Zebra-consensus
- Zfnd Zebrad
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-40880?
- CVE-2026-40880 is a high-severity vulnerability in Zcashfoundation Zebra-Consensus, classified under CWE-1025. CVSS score: 8.1/10. Published 2026-04-21.
- How severe is CVE-2026-40880?
- High severity. CVSS v3 base score is 8.1 out of 10.