# CVE-2006-4021: Weak cryptography in n/a

> Attackers can identify message patterns in ScatterChat via birthday attacks on its custom ECB padding, compromising data confidentiality.

- **Severity:** Low 2.6 (`AV:N/AC:H/Au:N/C:P/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Aug 2006
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-r4jq-cqww-9m6q

## What is CVE-2006-4021?

CVE-2006-4021 is a low-severity vulnerability in n/a, published on 17 Aug 2006. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The cryptographic module in ScatterChat 1.0.x allows attackers to identify patterns in large numbers of messages by identifying collisions using a birthday attack on the custom padding mechanism for ECB mode encryption.

## Which versions are affected by CVE-2006-4021?

It affects 1 product.


Products: Scatterchat Scatterchat.

## How do I fix CVE-2006-4021?

No fix has been published for CVE-2006-4021 yet. Limit exposure of the affected software until one is available.

## Is CVE-2006-4021 being exploited?

There is no known exploitation of CVE-2006-4021 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2006-4508](https://insights.sbomify.com/CVE-2006-4508/): Denial of service in n/a (medium 4.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2006-4021 and fix it if it is affected.

What it is: CVE-2006-4021 is a low-severity vulnerability in n/a, published on 17 Aug 2006. 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-2006-4021 in the wild and no public exploit code.

Affected product: n/a. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2006-4021/ (Markdown: https://insights.sbomify.com/CVE-2006-4021/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2006-4021
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2006-4021
- OSV: https://osv.dev/vulnerability/CVE-2006-4021

---
From sbomify Insights: https://insights.sbomify.com/CVE-2006-4021/
Summaries are generated and may contain mistakes; the official description above is the record.