# CVE-2025-36854: EOL ASP.NET 6.0 Remote Code Execution Vulnerability > A race condition in ASP.NET Core allows remote code execution via use-after-free when closing HTTP/3 streams, affecting end-of-life software. - **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 8 Sep 2025 - **Updated:** 8 Sep 2025 - **Also known as:** BIT-dotnet-2025-36854, BIT-dotnet-sdk-2025-36854, GHSA-qwjg-j8g7-hwvh ## What is CVE-2025-36854? CVE-2025-36854 is a high-severity use after free vulnerability in Microsoft .NET 6.0, published on 8 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description A vulnerability ( CVE-2024-38229 https://www.cve.org/CVERecord ) exists in EOL ASP.NET when closing an HTTP/3 stream while application code is writing to the response body, a race condition may lead to use-after-free, resulting in Remote Code Execution. Per CWE-416: Use After Free https://cwe.mitre.org/data/definitions/416.html , Use After Free is when a product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. This issue affects EOL ASP.NET 6.0.0 <= 6.0.36 as represented in this CVE, as well as 8.0.0 <= 8.0.8, 9.0.0-preview.1.24081.5 <= 9.0.0.RC.1 as represented in  CVE-2024-38229 https://www.cve.org/CVERecord . Additionally, if you've deployed self-contained applications https://docs.microsoft.com/dotnet/core/deploying/#self-contained-deployments-scd  targeting any of the impacted versions, these applications are also vulnerable and must be recompiled and redeployed. NOTE: This CVE only represents End Of Life (EOL) software components. The vendor, Microsoft, has indicated there will be no future updates nor support provided upon inquiry. Weakness: CWE-416 (Use After Free) ## Which versions are affected by CVE-2025-36854? 2 open source packages ship an affected version, including dotnet and dotnet-sdk. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `dotnet` | Bitnami | From 6.0.0 | 8.0.1 | | `dotnet-sdk` | Bitnami | From 6.0.0 | 6.0.418 | ## How do I fix CVE-2025-36854? Upgrade dotnet to 8.0.1 or later. ## Is CVE-2025-36854 being exploited? There is no known exploitation of CVE-2025-36854 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2025-36854 and fix it if it is affected. What it is: CVE-2025-36854 is a high-severity use after free vulnerability in Microsoft .NET 6.0, published on 8 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2025-36854 in the wild and no public exploit code. Affected packages and fixed versions: - dotnet (Bitnami): affected from 6.0.0; fixed in 8.0.1 - dotnet-sdk (Bitnami): affected from 6.0.0; fixed in 6.0.418 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-2025-36854/ (Markdown: https://insights.sbomify.com/CVE-2025-36854/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2025-36854 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-36854 - OSV: https://osv.dev/vulnerability/CVE-2025-36854 --- From sbomify Insights: https://insights.sbomify.com/CVE-2025-36854/ Summaries are generated and may contain mistakes; the official description above is the record.