# Microsoft Security Advisory CVE-2025-21176 | .NET and Visual Studio Remote Code Execution Vulnerability

Advisory record · `GHSA-gjf6-3w4p-7xfh`

- **Identifiers:** `GHSA-gjf6-3w4p-7xfh` · `BIT-dotnet-2025-21176` · `BIT-dotnet-sdk-2025-21176` · `CVE-2025-21176`
- **State:** Confirmed
- **Severity:** CVSS 8.8 High
- **Critical:** No
- **Weakness (CWE):** [CWE-126](https://cwe.mitre.org/data/definitions/126.html)
- **Tags:** [CWE-126](https://agentprime.io/advisories/tag/cwe-126.md)
- **Published:** 14 Jan 2025
- **Updated:** 10 Sept 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 14 Jan 2025, 19:46 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `Microsoft.NetCore.App.Runtime.linux-arm` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.linux-arm64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.linux-musl-arm` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.linux-musl-arm64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.linux-musl-x64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.linux-x64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.osx-arm64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.osx-x64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.win-arm` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.win-arm64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.win-x64` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`
- `Microsoft.NetCore.App.Runtime.win-x86` (NuGet): affected `>=9.0.0, <9.0.1 || >=8.0.0, <8.0.12`; fixed in `9.0.1`, `8.0.12`

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 8.8 High, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C`, from CNA (microsoft)

- **CISA KEV:** Not listed.
- **EPSS:** 0.024, the 84th percentile, on 8 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 14 Jan 2025, 18:26 UTC: [Published by the maintainers as a GitHub repository advisory](https://github.com/dotnet/runtime/security/advisories/GHSA-gjf6-3w4p-7xfh)
- 31 Oct 2026, 15:21 UTC: First seen by agentprime
- 31 Oct 2026, 15:21 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-gjf6-3w4p-7xfh)

## Sources

- [GitHub Advisory Database: GHSA-gjf6-3w4p-7xfh](https://github.com/advisories/GHSA-gjf6-3w4p-7xfh)
- [OSV: GHSA-gjf6-3w4p-7xfh](https://osv.dev/vulnerability/GHSA-gjf6-3w4p-7xfh)
- <https://github.com/dotnet/runtime/security/advisories/GHSA-gjf6-3w4p-7xfh>
- <https://nvd.nist.gov/vuln/detail/CVE-2025-21176>
- <https://github.com/dotnet/runtime>
- <https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21176>
- <https://www.herodevs.com/vulnerability-directory/cve-2025-21176>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-gjf6-3w4p-7xfh>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-gjf6-3w4p-7xfh/>. Everything for agents: <https://agentprime.io/llms.txt>.