Vulnerability · Published Oct 2, 2026 · Assigned by VulnCheck
CVE-2026-104437Zebra before 4.4.0 Consensus Split via SIGHASH_SINGLE Missing-Output Handling
High 7.4
In plain English
A high-severity security flaw in zebra from ZcashFoundation. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities).
Severity (CVSS 3.1)7.4High
Exploit odds (30 days)0.2%top 83.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| ZcashFoundation | zebra | 0 – before 4.4.0 |
Weakness: CWE-347 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
References
- GitHub Security Advisory (GHSA-cwfq-rfcr-8hmp) vendor-advisory
- VulnCheck Advisory: Zebra before 4.4.0 Consensus Split via SIGHASH_SINGLE Missing-Output Handling third-party-advisory