# CVE-2006-2421: Memory corruption in n/a

> Remote attackers can execute arbitrary code on FortressSSH servers by sending long SSH_MSG_KEXINIT messages that trigger a stack-based buffer overflow during logging.

- **Severity:** High 7.5 (`AV:N/AC:L/Au:N/C:P/I:P/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 May 2006
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-4r73-xvcj-763w

## What is CVE-2006-2421?

CVE-2006-2421 is a high-severity memory corruption vulnerability in n/a, published on 17 May 2006. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Stack-based buffer overflow in Pragma FortressSSH 4.0.7.20 allows remote attackers to execute arbitrary code via long SSH_MSG_KEXINIT messages, which may cause an overflow when being logged.  NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.

## Which versions are affected by CVE-2006-2421?

It affects 1 product.


Products: Pragma Systems Fortressssh.

## How do I fix CVE-2006-2421?

No fix has been published for CVE-2006-2421 yet. Limit exposure of the affected software until one is available.

## Is CVE-2006-2421 being exploited?

There is no known exploitation of CVE-2006-2421 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2006-2421 and fix it if it is affected.

What it is: CVE-2006-2421 is a high-severity memory corruption vulnerability in n/a, published on 17 May 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-2006-2421 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-2006-2421/ (Markdown: https://insights.sbomify.com/CVE-2006-2421/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2006-2421
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2006-2421
- OSV: https://osv.dev/vulnerability/CVE-2006-2421

---
From sbomify Insights: https://insights.sbomify.com/CVE-2006-2421/
Summaries are generated and may contain mistakes; the official description above is the record.