# GHSA-84x2-2qv6-qg56: Nervos CKB P2P DoS Attacks

> Attackers can cause denial of service on Nervos CKB nodes by flooding the P2P network with random transaction hashes due to missing rate limits.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Feb 2024

## What is GHSA-84x2-2qv6-qg56?

GHSA-84x2-2qv6-qg56 is a denial of service vulnerability in ckb, published on 2 Feb 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The P2P protocols lack of rate limit. For example, in relay protocol, when a node receives a broadcasted `tx_hashes`, it will mark it in memory to avoid duplicated requests. [code → ](https://github.com/nervosnetwork/ckb/blob/26e4837212c392c3c706a0da7a056131fb060433/sync/src/relayer/transactions_process.rs#L67).

It is easy to establish a DoS attach by generating random tx hashes.

### Impact

It affects all nodes connected to the P2P network.

### Workarounds

Apply rate limit on the data sent to CKB P2P port.

## Which versions are affected by GHSA-84x2-2qv6-qg56?

2 open source packages ship an affected version, including ckb.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ckb` | crates.io | All versions | 0.34.0 |
| `ckb` | crates.io | All versions | 0.34.0 |

## How do I fix GHSA-84x2-2qv6-qg56?

Upgrade ckb to 0.34.0 or later.

## Is GHSA-84x2-2qv6-qg56 being exploited?

There is no known exploitation of GHSA-84x2-2qv6-qg56 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-84x2-2qv6-qg56 and fix it if it is affected.

What it is: GHSA-84x2-2qv6-qg56 is a denial of service vulnerability in ckb, published on 2 Feb 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-84x2-2qv6-qg56 in the wild and no public exploit code.

Affected packages and fixed versions:
- ckb (crates.io): affected all versions; fixed in 0.34.0
- ckb (crates.io): affected all versions; fixed in 0.34.0

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/GHSA-84x2-2qv6-qg56/ (Markdown: https://insights.sbomify.com/GHSA-84x2-2qv6-qg56/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-84x2-2qv6-qg56

---
From sbomify Insights: https://insights.sbomify.com/GHSA-84x2-2qv6-qg56/
Summaries are generated and may contain mistakes; the official description above is the record.