# CVE-2021-41173: DoS via maliciously crafted p2p message

> A remote attacker can crash a Go Ethereum node by sending a maliciously crafted peer-to-peer message, requiring an upgrade to mitigate.

- **Severity:** Medium 5.7 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 26 Oct 2021
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-59hh-656j-3p7v, GO-2022-0256

## What is CVE-2021-41173?

CVE-2021-41173 is a medium-severity denial of service vulnerability in go-ethereum, published on 26 Oct 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Go Ethereum is the official Golang implementation of the Ethereum protocol. Prior to version 1.10.9, a vulnerable node is susceptible to crash when processing a maliciously crafted message from a peer. Version v1.10.9 contains patches to the vulnerability. There are no known workarounds aside from upgrading.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2021-41173?

3 open source packages ship an affected version, including github.com/ethereum/go-ethereum. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/ethereum/go-ethereum` | Go | All versions | 1.10.9 |
| `github.com/ethereum/go-ethereum` | Go | All versions | 1.10.9 |
| `github.com/ethereum/go-ethereum` | Go | All versions | 1.10.9 |

Products: Ethereum Go Ethereum.

## How do I fix CVE-2021-41173?

Upgrade github.com/ethereum/go-ethereum to 1.10.9 or later.

## Is CVE-2021-41173 being exploited?

There is no known exploitation of CVE-2021-41173 in the wild and no public exploit code.

## Other vulnerabilities in go-ethereum

- [CVE-2026-26314](https://insights.sbomify.com/CVE-2026-26314/): Go Ethereum affected by DoS via malicious p2p message (high 8.7)
- [CVE-2023-42319](https://insights.sbomify.com/CVE-2023-42319/): go-ethereum vulnerable to denial of service via crafted GraphQL query (high 7.5)
- [CVE-2023-40591](https://insights.sbomify.com/CVE-2023-40591/): Denial of service via malicious p2p message in go-ethereum (high 7.5)
- [CVE-2021-42219](https://insights.sbomify.com/CVE-2021-42219/): Denial of service in go-ethereum (high 7.5)
- [CVE-2022-23327](https://insights.sbomify.com/CVE-2022-23327/): Denial of Service in Go-Ethereum (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-41173 and fix it if it is affected.

What it is: CVE-2021-41173 is a medium-severity denial of service vulnerability in go-ethereum, published on 26 Oct 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-41173 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/ethereum/go-ethereum (Go): affected all versions; fixed in 1.10.9
- github.com/ethereum/go-ethereum (Go): affected all versions; fixed in 1.10.9
- github.com/ethereum/go-ethereum (Go): affected all versions; fixed in 1.10.9

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-2021-41173/ (Markdown: https://insights.sbomify.com/CVE-2021-41173/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-41173
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-41173
- OSV: https://osv.dev/vulnerability/CVE-2021-41173

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-41173/
Summaries are generated and may contain mistakes; the official description above is the record.