# GHSA-h4c3-5275-vrmg: Nervos CKB Pool does not remove the conflicting transactions from the statistics

> An attacker can cause the Nervos CKB transaction pool to fill up and reject all new transactions by exploiting a statistics tracking bug.

- **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:** 3 Feb 2024

## What is GHSA-h4c3-5275-vrmg?

GHSA-h4c3-5275-vrmg is a denial of service vulnerability in ckb, published on 3 Feb 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

### Impact

There's a bug in the pool statistics that when conflicting transactions are removed from the pool, they are not subtracted from the statics. Finally, the transaction pool keeps full and reject all transactions.

### Patches

0.39.2

### Workarounds

Restart the CKB node.

## Which versions are affected by GHSA-h4c3-5275-vrmg?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ckb` | crates.io | All versions | 0.39.2 |
| `ckb` | crates.io | All versions | 0.39.2 |

## How do I fix GHSA-h4c3-5275-vrmg?

Upgrade ckb to 0.39.2 or later.

## Is GHSA-h4c3-5275-vrmg being exploited?

There is no known exploitation of GHSA-h4c3-5275-vrmg in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-h4c3-5275-vrmg and fix it if it is affected.

What it is: GHSA-h4c3-5275-vrmg is a denial of service vulnerability in ckb, published on 3 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-h4c3-5275-vrmg in the wild and no public exploit code.

Affected packages and fixed versions:
- ckb (crates.io): affected all versions; fixed in 0.39.2
- ckb (crates.io): affected all versions; fixed in 0.39.2

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-h4c3-5275-vrmg/ (Markdown: https://insights.sbomify.com/GHSA-h4c3-5275-vrmg/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-h4c3-5275-vrmg

---
From sbomify Insights: https://insights.sbomify.com/GHSA-h4c3-5275-vrmg/
Summaries are generated and may contain mistakes; the official description above is the record.