# CVE-2026-40369: Windows Kernel Elevation of Privilege Vulnerability

> A heap-based buffer overflow in the Windows Kernel allows an authorized local attacker to elevate privileges.

- **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:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 May 2026
- **Updated:** 10 Aug 2026
- **Also known as:** GHSA-4qhv-qjg6-r699

## What is CVE-2026-40369?

CVE-2026-40369 is a high-severity memory corruption vulnerability in Microsoft Windows 11 24h2, published on 12 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

Weakness: CWE-822 (Untrusted Pointer Dereference)

## Which versions are affected by CVE-2026-40369?

It affects 4 products.


Products: Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows 11 26h1, Microsoft Windows Server 2025.

## How do I fix CVE-2026-40369?

No fix has been published for CVE-2026-40369 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-40369 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40369 exists.

Public exploit code:

- Full exploit code for CVE-2026-40369 - A Windows kernel arbitrary write vulnerability that allows browser sandbox escape from all browsers render process sandbox (github_poc): https://github.com/orinimron123/CVE-2026-40369-EXPLOIT
- 🛡️ Official AI Security Tool module for CVE-2026-40369 (Windows NtQuerySystemInformation Class 253 Arbitrary Kernel Address Increment LPE Primitive). (github_poc): https://github.com/ZeroDayEvil/CVE-2026-40369-EXPLOIT
- eprocess offset puller for relevant member offsets and function addresses for cve-2026-40369 (github_poc): https://github.com/piffd0s/ntoskrnl-metadata
- CVE-2026-40369 (github_poc): https://github.com/0xredash/CVE-2026-40369
- https://github.com/ercihan/CVE-2026-40369 (github_poc): https://github.com/ercihan/CVE-2026-40369
- CVE-2026-40369本地权限提升漏洞exp (github_poc): https://github.com/CCELEND/CVE-2026-40369

## Other vulnerabilities in Microsoft Windows 11 24h2

- [CVE-2025-60710](https://insights.sbomify.com/CVE-2025-60710/): Microsoft Windows Link Following (high 7.8, exploited in the wild)
- [CVE-2026-54990](https://insights.sbomify.com/CVE-2026-54990/): Remote Desktop Client Remote Code Execution Vulnerability (critical 9.8)
- [CVE-2025-50165](https://insights.sbomify.com/CVE-2025-50165/): Windows Graphics Component Remote Code Execution Vulnerability (critical 9.8)
- [CVE-2025-21311](https://insights.sbomify.com/CVE-2025-21311/): Windows NTLM V1 Elevation of Privilege Vulnerability (critical 9.8)
- [CVE-2026-108463](https://insights.sbomify.com/CVE-2026-108463/): Windows SmartScreen Security Feature Bypass Vulnerability (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-40369 and fix it if it is affected.

What it is: CVE-2026-40369 is a high-severity memory corruption vulnerability in Microsoft Windows 11 24h2, published on 12 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40369 exists.

Affected product: Microsoft Windows 11 24h2. 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-2026-40369/ (Markdown: https://insights.sbomify.com/CVE-2026-40369/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-40369
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-40369
- OSV: https://osv.dev/vulnerability/CVE-2026-40369

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-40369/
Summaries are generated and may contain mistakes; the official description above is the record.