# CVE-2009-4009: Memory corruption in n/a

> Remote attackers can cause denial of service or execute arbitrary code via crafted packets in PowerDNS Recursor.

- **Severity:** Critical 10.0 (`AV:N/AC:L/Au:N/C:C/I:C/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 Jan 2010
- **Updated:** 7 Aug 2024
- **Also known as:** DEBIAN-CVE-2009-4009, GHSA-x753-v6ch-rpgq

## What is CVE-2009-4009?

CVE-2009-4009 is a critical memory corruption vulnerability in Powerdns Recursor, published on 8 Jan 2010. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Buffer overflow in PowerDNS Recursor before 3.1.7.2 allows remote attackers to cause a denial of service (daemon crash) or possibly execute arbitrary code via crafted packets.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2009-4009?

It affects 1 product.


Products: Powerdns Recursor.

## How do I fix CVE-2009-4009?

Upgrade to a fixed version.

## Is CVE-2009-4009 being exploited?

There is no known exploitation of CVE-2009-4009 in the wild and no public exploit code.

## Other vulnerabilities in Powerdns Recursor

- [CVE-2020-10030](https://insights.sbomify.com/CVE-2020-10030/): Memory corruption in n/a (high 8.8)
- [CVE-2025-59023](https://insights.sbomify.com/CVE-2025-59023/): Crafted delegations or IP fragments can poison cached delegations in Recursor (high 8.2)
- [CVE-2025-59030](https://insights.sbomify.com/CVE-2025-59030/): Insufficient validation of incoming notifies over TCP can lead to a denial of service in Recursor (high 7.5)
- [CVE-2023-22617](https://insights.sbomify.com/CVE-2023-22617/): Denial of service in n/a (high 7.5)
- [CVE-2018-16855](https://insights.sbomify.com/CVE-2018-16855/): Memory corruption in pdns-recursor (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-4009 and fix it if it is affected.

What it is: CVE-2009-4009 is a critical memory corruption vulnerability in Powerdns Recursor, published on 8 Jan 2010. 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-2009-4009 in the wild and no public exploit code.

Affected product: Powerdns Recursor. 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-2009-4009/ (Markdown: https://insights.sbomify.com/CVE-2009-4009/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-4009
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-4009
- OSV: https://osv.dev/vulnerability/CVE-2009-4009

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-4009/
Summaries are generated and may contain mistakes; the official description above is the record.