CVE-2026-40880 json
Zebra: Cached Mempool Verification Bypasses Consensus Rules for Ahead-of-Tip Blocks
published 2026-04-18 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-24266 , GHSA-xvj8-ph7x-65gf
- cvss
- 8.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 17%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- crates.io zebra-consensus 5.0.2
- crates.io zebrad 4.3.1
- zfnd zebra-consensus 5.0.2
- zfnd zebra 5.0.2
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.26% chance of exploitation in the next 30 days, higher than 17% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H |
| CNA | 4.0 | 7.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| crates.io | zebra-consensus | <5.0.2 |
5.0.2 |
| crates.io | zebrad | <4.3.1 |
4.3.1 |
Affected products
- ZcashFoundation zebrad
- ZcashFoundation zebra-consensus
Classification
- Weakness
-
- CWE-1025 Comparison Using Wrong Factors
References
-
github.com
/ZcashFoundation/zebra/security/advisories/GHSA-xvj8-ph7x-65gf
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-40880
advisory
-
github.com
/ZcashFoundation/zebra
package
Sources
- CVE List CVE-2026-40880
- GitHub Advisory GHSA-xvj8-ph7x-65gf
- NVD CVE-2026-40880
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.