# GHSA-7fw6-6mfj-g3q2: ckb: Transaction header_deps validation issue (network forking)

> Attackers can cause network forking by submitting transactions with invalid header dependencies, disrupting consensus in CKB nodes.

- **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 Nov 2022

## What is GHSA-7fw6-6mfj-g3q2?

GHSA-7fw6-6mfj-g3q2 is a vulnerability in ckb, published on 2 Nov 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

### Impact
fn `HeaderChecker#check_valid` skipped main chain checking after this PR: https://github.com/nervosnetwork/ckb/pull/1646/files#diff-c4e017b67c1b3005ca0c446a9b0879571aa36a858b1f7ddd1b9328a884e3214bR171-R176

It will cause network forking if one transaction is using a forked block header which is not exists in local node's storage.

### Patches

0.101.1 and later versions

## Which versions are affected by GHSA-7fw6-6mfj-g3q2?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `ckb` | crates.io | All versions | 0.101.1 |
| `ckb` | crates.io | All versions | 0.101.1 |

## How do I fix GHSA-7fw6-6mfj-g3q2?

Upgrade ckb to 0.101.1 or later.

## Is GHSA-7fw6-6mfj-g3q2 being exploited?

There is no known exploitation of GHSA-7fw6-6mfj-g3q2 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-7fw6-6mfj-g3q2 and fix it if it is affected.

What it is: GHSA-7fw6-6mfj-g3q2 is a vulnerability in ckb, published on 2 Nov 2022. 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-7fw6-6mfj-g3q2 in the wild and no public exploit code.

Affected packages and fixed versions:
- ckb (crates.io): affected all versions; fixed in 0.101.1
- ckb (crates.io): affected all versions; fixed in 0.101.1

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-7fw6-6mfj-g3q2/ (Markdown: https://insights.sbomify.com/GHSA-7fw6-6mfj-g3q2/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-7fw6-6mfj-g3q2

---
From sbomify Insights: https://insights.sbomify.com/GHSA-7fw6-6mfj-g3q2/
Summaries are generated and may contain mistakes; the official description above is the record.