CVE-2026-104437

Zebra before 4.4.0 contains a consensus divergence vulnerability in V5 transparent signature verification, computing a ZIP-244 digest for SIGHASH_SINGLE inputs lacking corresponding outputs instead of failing. Attackers can craft V5 transactions with fewer outputs than inputs that Zebra accepts and templates via getblocktemplate, producing blocks zcashd rejects.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-cwfq-rfcr-8hmp
https://www.vulncheck.com/advisories/zebra-before-4.4.0-consensus-split-via-sighash-single-missing-output-handling
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-cwfq-rfcr-8hmp

Configurations

No configuration.

History

06 Oct 2026, 03:17

Type	Values Removed	Values Added
References	~~() https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-cwfq-rfcr-8hmp -~~	() https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-cwfq-rfcr-8hmp -

02 Oct 2026, 12:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 12:17

Updated : 2026-10-06 03:17

NVD link : CVE-2026-104437

Mitre link : CVE-2026-104437

CVE.ORG link : CVE-2026-104437

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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