# CVE-2026-44500: ZEBRA: Allocation Amplification in Inbound Network Deserializers

> An attacker can cause a Zcash node to crash or become unresponsive by forcing excessive memory allocation during network deserialization.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 May 2026
- **Updated:** 8 May 2026
- **Also known as:** GHSA-438q-jx8f-cccv

## What is CVE-2026-44500?

CVE-2026-44500 is a medium-severity denial of service 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, prior to zebra-chain version 7.0.0, and prior to zebra-network version 6.0.0, several inbound deserialization paths in Zebra allocated buffers sized against generic transport or block-size ceilings before the tighter protocol or consensus limits were enforced. An unauthenticated or post-handshake peer could therefore force the node to preallocate and parse for orders of magnitude more data than the protocol intended, across headers messages, equihash solutions in block headers, Sapling spend vectors in V5/V4 transactions, and coinbase script bytes in blocks. This issue has been patched in zebrad version 4.4.0, zebra-chain version 7.0.0, and zebra-network version 6.0.0.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-44500?

6 open source packages ship an affected version, including zebra-chain, zebra-network and zebrad. It affects 3 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `zebra-chain` | crates.io | All versions | 7.0.0 |
| `zebra-chain` | crates.io | All versions | 7.0.0 |
| `zebra-network` | crates.io | All versions | 6.0.0 |
| `zebra-network` | crates.io | All versions | 6.0.0 |
| `zebrad` | crates.io | All versions | 4.4.0 |
| `zebrad` | crates.io | All versions | 4.4.0 |

Products: Zfnd Zebra-Chain, Zfnd Zebra-Network, Zfnd Zebrad.

## How do I fix CVE-2026-44500?

Upgrade zebra-chain to 7.0.0 or later.

## Is CVE-2026-44500 being exploited?

There is no known exploitation of CVE-2026-44500 in the wild and no public exploit code.

## Other vulnerabilities in ZcashFoundation zebra

- [CVE-2026-41584](https://insights.sbomify.com/CVE-2026-41584/): ZEBRA: rk Identity Point Panic in Transaction Verification (critical 9.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-44500 and fix it if it is affected.

What it is: CVE-2026-44500 is a medium-severity denial of service 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.
Exploitation: There is no known exploitation of CVE-2026-44500 in the wild and no public exploit code.

Affected packages and fixed versions:
- zebra-chain (crates.io): affected all versions; fixed in 7.0.0
- zebra-chain (crates.io): affected all versions; fixed in 7.0.0
- zebra-network (crates.io): affected all versions; fixed in 6.0.0
- zebra-network (crates.io): affected all versions; fixed in 6.0.0
- zebrad (crates.io): affected all versions; fixed in 4.4.0
- zebrad (crates.io): affected all versions; fixed in 4.4.0

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-44500/ (Markdown: https://insights.sbomify.com/CVE-2026-44500/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-44500
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-44500
- OSV: https://osv.dev/vulnerability/CVE-2026-44500

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-44500/
Summaries are generated and may contain mistakes; the official description above is the record.