Vulnerability in Zebra (CVE-2026-104437)
Summary
Vulnerability in Zebra (CVE-2026-104437). Data can be tampered with by attackers.
Original description
The description as published by the source.
Zebra Transparent SIGHASH_SINGLE Corresponding-Output Handling Diverges From zcashd
Summary
For V5+ transparent spends, Zebra and zcashd disagree on the same consensus rule: SIGHASH_SINGLE must fail when the input index has no corresponding output. zcashd treats this as consensus-invalid under ZIP-244, while Zebra's transparent verification path computes a digest for the missing-output case instead of failing.
The result is a direct block-validity split. A malformed V5 transparent transaction can be accepted by Zebra, retained in Zebra's mempool, selected into Zebra getblocktemplate, mined into a block, and then rejected by zcashd.
Details
Validated code revisions used during analysis:
zcashd:2c63e9aa08cb170b0feb374161bea94720c3e1f5Zebra:a905fa19e3a91c7b4ead331e2709e6dec5db12cb
Scope note:
- earlier triage material grouped pre-V5 and V5 behavior together;
- re-execution on the pinned revisions did not reproduce the claimed pre-V5 / V4 reject-side behavior;
- this advisory therefore covers the V5+ / ZIP-244 variant only.
zcashd side:
- Transparent scripts in blocks are checked through
TransactionSignatureChecker::CheckSig()andSignatureHash():zcash/src/script/interpreter.cpp. - In the ZIP-244 branch,
SignatureHash()explicitly throws whenSIGHASH_SINGLEorSIGHASH_SINGLE|ANYONECANPAYis…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-104437 has been found in Zebra.
Data can be tampered with by attackers. CVSS score: 7.4/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Zebra CVE-2026-104437" on the vendor's site.
CVE-2026-104437 (Zebra) — CWE-347 / CVSS v3 7.4
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-347) exists in Zebra.
Check the vendor advisory for the affected versions of Zebra.
Severity: High (CVSS 7.4/10). Data can be tampered with by attackers.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Zebra' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Zebra' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Zebraを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- package github.com
- web github.com
- web disclosure@vulncheck.com
- web nvd.nist.gov
- web github.com
- web github.com