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

What is CVE-2026-44497?

CVE-2026-44497 is a critical vulnerability in ZcashFoundation zebra, published on 8 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

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.

Weakness: CWE-347

Which versions are affected by CVE-2026-44497?

4 open source packages ship an affected version, including zebra-script and zebrad. It affects 2 products.

Products include Zfnd Zebra-Script, Zfnd Zebrad.

How do I fix CVE-2026-44497?

Upgrade zebra-script to 6.0.0 or later.

Is CVE-2026-44497 being exploited?

There is no known exploitation of CVE-2026-44497 in the wild and no public exploit code.

Other vulnerabilities in ZcashFoundation zebra

• CVE-2026-41583 ZEBRA: Consensus Divergence in Transparent Sighash Hash-Type Handling Critical 9.3

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-gq4h-3grw-2rhv.