Zebra v4.4.0 still accepts V5 SIGHASH_SINGLE without a corresponding output
Zebra v4.4.0 still accepts V5 SIGHASH_SINGLE without a corresponding output. Zebra failed to enforce a ZIP-244 consensus rule for V5 transparent transactions: when an input is signed with SIGHASHSINGLE and there is no transparent output at the same index as that input, validation must fail.
Vuln-watch · relayed from the GitHub Advisory Database; see Source & attribution below
Summary
Zebra failed to enforce a ZIP-244 consensus rule for V5 transparent transactions: when an input is signed with SIGHASHSINGLE and there is no transparent output at the same index as that input, validation must fail.
Affected
- zebrad (rust) < 4.4.1 — fixed in 4.4.1
- zebra-script (rust) < 6.0.1 — fixed in 6.0.1
Severity
Critical (CVSS 9.3), as rated by the upstream advisory.
Recommended actions
- Upgrade zebrad to 4.4.1 or later
- Upgrade zebra-script to 6.0.1 or later
Source & attribution
This 0xCERT advisory summarises GHSA-pvmv-cwg8-v6c8 from the GitHub Advisory Database, credited upstream to sangsoo-osec, fivelittleducks: https://github.com/advisories/GHSA-pvmv-cwg8-v6c8. Details may change; refer to the original source for the authoritative record.
References
OpenPGP-signed. The signed text of this advisory verifies against the 0xCERT key CCC7 D9EC 9415 723D.
Published 2026-05-08 · last updated 2026-10-08
curl -s https://www.0xcert.com/pgp.asc | gpg --import && curl -s https://www.0xcert.com/advisory/0xCERT-2026-0195/signed.txt | gpg --verify