Vulnerability · Published May 8, 2026 · Assigned by GitHub_M

CVE-2026-44497ZEBRA: Consensus Divergence in Transparent Sighash Hash-Type Handling due to Stale Buffer

Critical 9.3

In plain English

A critical-severity security flaw in zebra from ZcashFoundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).

Severity (CVSS 4.0)9.3Critical

Exploit odds (30 days)0.2%top 91.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
ZcashFoundation	zebra	zebra-script < 6.0.0zebrad < 4.4.0

Weakness: CWE-347 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:H/SA:H

References

https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-gq4h-3grw-2rhv x_refsource_CONFIRM