# CVE-2019-0803: Microsoft Win32k Privilege Escalation

> Attackers can exploit a Win32k memory handling flaw to gain elevated privileges on Windows systems.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 3 Nov 2021 (CISA KEV), used in ransomware
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Apr 2019
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-6h99-5j8v-7r3p

## What is CVE-2019-0803?

CVE-2019-0803 is a high-severity vulnerability in Microsoft Windows 10 1507, published on 9 Apr 2019. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0685, CVE-2019-0859.

## Which versions are affected by CVE-2019-0803?

It affects 15 products.


Products: Microsoft Windows 10 1507, Microsoft Windows 10 1607, Microsoft Windows 10 1703, Microsoft Windows 10 1709, Microsoft Windows 10 1803, Microsoft Windows 10 1809, Microsoft Windows 7, Microsoft Windows 8.1, Microsoft Windows Rt 8.1, Microsoft Windows Server 1709, Microsoft Windows Server 1803, Microsoft Windows Server 2008, Microsoft Windows Server 2012, Microsoft Windows Server 2016, Microsoft Windows Server 2019.

## How do I fix CVE-2019-0803?

No fix has been published for CVE-2019-0803 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 3 May 2022.

## Is CVE-2019-0803 being exploited?

Yes. Attackers have exploited CVE-2019-0803 in the wild since at least 3 Nov 2021, including in ransomware campaigns.

Public exploit code:

- Win32k Elevation of Privilege Poc (github_poc): https://github.com/ExpLife0011/CVE-2019-0803
- Win32k Elevation of Privilege Poc (github_poc): https://github.com/Iamgublin/CVE-2019-0803
- Microsoft Windows - 'Win32k' Local Privilege Escalation (exploitdb)

## Other vulnerabilities in Microsoft Windows 10 1507

- [CVE-2017-8543](https://insights.sbomify.com/CVE-2017-8543/): Microsoft Windows Search Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2025-33053](https://insights.sbomify.com/CVE-2025-33053/): Microsoft Windows External Control of File Name or Path (high 8.8, exploited in the wild)
- [CVE-2025-33073](https://insights.sbomify.com/CVE-2025-33073/): Microsoft Windows SMB Client Improper Access Control (high 8.8, exploited in the wild)
- [CVE-2024-49039](https://insights.sbomify.com/CVE-2024-49039/): Microsoft Windows Task Scheduler Privilege Escalation (high 8.8, exploited in the wild)
- [CVE-2024-43461](https://insights.sbomify.com/CVE-2024-43461/): Microsoft Windows MSHTML Platform Spoofing (high 8.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-0803 and fix it if it is affected.

What it is: CVE-2019-0803 is a high-severity vulnerability in Microsoft Windows 10 1507, published on 9 Apr 2019. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2019-0803 in the wild since at least 3 Nov 2021, including in ransomware campaigns.

Affected product: Microsoft Windows 10 1507. 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-2019-0803/ (Markdown: https://insights.sbomify.com/CVE-2019-0803/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-0803
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-0803
- OSV: https://osv.dev/vulnerability/CVE-2019-0803

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From sbomify Insights: https://insights.sbomify.com/CVE-2019-0803/
Summaries are generated and may contain mistakes; the official description above is the record.