# CVE-2023-36802: Microsoft Streaming Service Proxy Privilege Escalation

> An attacker can exploit a use-after-free flaw in the Microsoft Streaming Service Proxy 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/E:U/RL:O/RC:C`)
- **Exploited in the wild:** Yes, since 12 Sep 2023 (CISA KEV)
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Sep 2023
- **Updated:** 30 Oct 2025
- **Also known as:** GHSA-4v34-9x49-p452

## What is CVE-2023-36802?

CVE-2023-36802 is a high-severity use after free vulnerability in Microsoft Windows 10 1809, published on 12 Sep 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Microsoft Streaming Service Proxy Elevation of Privilege Vulnerability

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2023-36802?

It affects 7 products.


Products: Microsoft Windows 10 1809, Microsoft Windows 10 21h2, Microsoft Windows 10 22h2, Microsoft Windows 11 21h2, Microsoft Windows 11 22h2, Microsoft Windows Server 2019, Microsoft Windows Server 2022.

## How do I fix CVE-2023-36802?

No fix has been published for CVE-2023-36802 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 3 Oct 2023.

## Is CVE-2023-36802 being exploited?

Yes. Attackers have exploited CVE-2023-36802 in the wild since at least 12 Sep 2023.

Public exploit code:

- LPE exploit for CVE-2023-36802 (github_poc): https://github.com/chompie1337/Windows_MSKSSRV_LPE_CVE-2023-36802
- Exploit for CVE-2023-36802 targeting MSKSSRV.SYS driver (github_poc): https://github.com/Nero22k/cve-2023-36802
- PoC for CVE-2023-36802 Microsoft Kernel Streaming Service Proxy (github_poc): https://github.com/x0rb3l/CVE-2023-36802-MSKSSRV-LPE
- CVE-2023-36802 ITW case (github_poc): https://github.com/4zur-0312/CVE-2023-36802
- Reverse engineering and vulnerability research on CVE-2023-36802, focusing on object type confusion in mksssrv.sys. (github_poc): https://github.com/rahul0xkr/Reproducing-CVE-2023-36802
- Old CVE, but new way to leak everything. (github_poc): https://github.com/nhh9905/CVE-2023-36802

## Other vulnerabilities in Microsoft Windows 10 1809

- [CVE-2024-29988](https://insights.sbomify.com/CVE-2024-29988/): Microsoft SmartScreen Prompt Security Feature Bypass (high 8.8, exploited in the wild)
- [CVE-2024-21412](https://insights.sbomify.com/CVE-2024-21412/): Microsoft Windows Internet Shortcut Files Security Feature Bypass (high 8.1, exploited in the wild)
- [CVE-2025-62221](https://insights.sbomify.com/CVE-2025-62221/): Microsoft Windows Use After Free (high 7.8, exploited in the wild)
- [CVE-2025-30400](https://insights.sbomify.com/CVE-2025-30400/): Microsoft Windows DWM Core Library Use-After-Free (high 7.8, exploited in the wild)
- [CVE-2024-21338](https://insights.sbomify.com/CVE-2024-21338/): Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-36802 and fix it if it is affected.

What it is: CVE-2023-36802 is a high-severity use after free vulnerability in Microsoft Windows 10 1809, published on 12 Sep 2023. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: Yes. Attackers have exploited CVE-2023-36802 in the wild since at least 12 Sep 2023.

Affected product: Microsoft Windows 10 1809. 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-2023-36802/ (Markdown: https://insights.sbomify.com/CVE-2023-36802/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-36802
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-36802
- OSV: https://osv.dev/vulnerability/CVE-2023-36802

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-36802/
Summaries are generated and may contain mistakes; the official description above is the record.