# CVE-2009-1537: Microsoft DirectX NULL Byte Overwrite

> Remote attackers can execute arbitrary code via a crafted QuickTime media file exploiting a NULL byte overwrite in the DirectX Movie Parser Filter.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 20 May 2026 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 29 May 2009
- **Updated:** 21 May 2026
- **Also known as:** GHSA-qvw7-mg6g-qm9m

## What is CVE-2009-1537?

CVE-2009-1537 is a high-severity memory corruption vulnerability in Microsoft Windows 2000, published on 29 May 2009. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Unspecified vulnerability in the QuickTime Movie Parser Filter in quartz.dll in DirectShow in Microsoft DirectX 7.0 through 9.0c on Windows 2000 SP4, Windows XP SP2 and SP3, and Windows Server 2003 SP2 allows remote attackers to execute arbitrary code via a crafted QuickTime media file, as exploited in the wild in May 2009, aka "DirectX NULL Byte Overwrite Vulnerability."

Weakness: CWE-158 (Improper Neutralization of Null Byte or NUL Character)

## Which versions are affected by CVE-2009-1537?

It affects 5 products.


Products: Microsoft Directx, Microsoft Windows 2000, Microsoft Windows 2003 Server, Microsoft Windows Server 2003, Microsoft Windows Xp.

## How do I fix CVE-2009-1537?

No fix has been published for CVE-2009-1537 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 3 Jun 2026.

## Is CVE-2009-1537 being exploited?

Yes. Attackers have exploited CVE-2009-1537 in the wild since at least 20 May 2026.

## Other vulnerabilities in Microsoft Windows 2000

- [CVE-2012-1537](https://insights.sbomify.com/CVE-2012-1537/): Memory corruption in n/a (critical 9.3)
- [CVE-2010-1879](https://insights.sbomify.com/CVE-2010-1879/): Code injection in n/a (critical 9.3)
- [CVE-2010-1880](https://insights.sbomify.com/CVE-2010-1880/): Code injection in n/a (critical 9.3)
- [CVE-2009-1538](https://insights.sbomify.com/CVE-2009-1538/): Memory corruption in n/a (critical 9.3)
- [CVE-2009-1539](https://insights.sbomify.com/CVE-2009-1539/): Code injection in n/a (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-1537 and fix it if it is affected.

What it is: CVE-2009-1537 is a high-severity memory corruption vulnerability in Microsoft Windows 2000, published on 29 May 2009. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: Yes. Attackers have exploited CVE-2009-1537 in the wild since at least 20 May 2026.

Affected product: Microsoft Windows 2000. 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-2009-1537/ (Markdown: https://insights.sbomify.com/CVE-2009-1537/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-1537
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-1537
- OSV: https://osv.dev/vulnerability/CVE-2009-1537

---
From sbomify Insights: https://insights.sbomify.com/CVE-2009-1537/
Summaries are generated and may contain mistakes; the official description above is the record.