Vulnerability in Zcashfoundation Zebra
CVE-2026-44497
ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.4.0 and prior to zebra-script version 6.0.0, the fix for CVE-2026-41583 introduced a separate issue due to insufficient error handling of the case where the sighash type is invalid, during sighash computation. Instead of returning an error, the normal flow would resume, and the input sighash buffer would be left untouched. In scenarios where a previous signature validation could leave a valid sighash in the buffer, an invalid hash-type could be incorrectly accepted, which would create a consensus split between Zebra and zcashd nodes. This issue has been patched in zebrad version 4.4.0 and zebra-script version 6.0.0.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.
EPSS exploit prediction
EPSS: 0.003 (21.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- Zcashfoundation Zebra — versions zebra-script < 6.0.0, zebrad < 4.4.0
- Zfnd Zebrad
- Zfnd Zebra-Script
Weakness classification (CWE)
References
- github.com/ZcashFoundation/zebra/security/advisories/GHSA-gq4h-3grw-2rhv (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-44497?
- CVE-2026-44497 is a critical-severity vulnerability in Zcashfoundation Zebra, classified under Improper Verification of Cryptographic Signature. CVSS score: 9.1/10. Published 2026-05-08.
- How severe is CVE-2026-44497?
- Critical severity. CVSS v3 base score is 9.1 out of 10.