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.

EPSS: 0.002 (8.4th percentile) — read the EPSS interpretation.

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.

Affected products

Weakness classification (CWE)

References

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.