# CVE-2009-1127: Null dereference in n/a

> Local attackers can gain elevated privileges by exploiting a NULL pointer dereference in the Windows kernel via a crafted application.

- **Severity:** High 7.2 (`AV:L/AC:L/Au:N/C:C/I:C/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Nov 2009
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-7cgh-j584-9v44

## What is CVE-2009-1127?

CVE-2009-1127 is a high-severity vulnerability in Microsoft Windows 2000, published on 11 Nov 2009. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

win32k.sys in the kernel in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold, SP1, and SP2, and Server 2008 Gold and SP2 does not correctly validate an argument to an unspecified system call, which allows local users to gain privileges via a crafted application that triggers a NULL pointer dereference, aka "Win32k NULL Pointer Dereferencing Vulnerability."

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2009-1127?

It affects 5 products.


Products: Microsoft Windows 2000, Microsoft Windows 2003 Server, Microsoft Windows Server 2008, Microsoft Windows Vista, Microsoft Windows Xp.

## How do I fix CVE-2009-1127?

No fix has been published for CVE-2009-1127 yet. Limit exposure of the affected software until one is available.

## Is CVE-2009-1127 being exploited?

There is no known exploitation of CVE-2009-1127 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft Windows 2000

- [CVE-2008-4250](https://insights.sbomify.com/CVE-2008-4250/): Microsoft Windows Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2010-0232](https://insights.sbomify.com/CVE-2010-0232/): Microsoft Windows Kernel Exception Handler (high 7.8, exploited in the wild)
- [CVE-2009-1123](https://insights.sbomify.com/CVE-2009-1123/): Microsoft Windows Improper Input Validation (high 7.8, exploited in the wild)
- [CVE-2002-0367](https://insights.sbomify.com/CVE-2002-0367/): Microsoft Windows Privilege Escalation (high 7.8, exploited in the wild)
- [CVE-2010-0269](https://insights.sbomify.com/CVE-2010-0269/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2009-1127 and fix it if it is affected.

What it is: CVE-2009-1127 is a high-severity vulnerability in Microsoft Windows 2000, published on 11 Nov 2009. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2009-1127 in the wild and no public exploit code.

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-2009-1127/ (Markdown: https://insights.sbomify.com/CVE-2009-1127/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2009-1127
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2009-1127
- OSV: https://osv.dev/vulnerability/CVE-2009-1127

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From sbomify Insights: https://insights.sbomify.com/CVE-2009-1127/
Summaries are generated and may contain mistakes; the official description above is the record.