CVE-2025-21171: Microsoft.NetCore.App.Runtime.linux arm Remote Code Execution Vulnerability
HIGHCVE-2025-21171 is a HIGH (CVSS 8.1) remote code execution vulnerability (CWE-122: Heap-based Buffer Overflow) affecting Microsoft.NetCore.App.Runtime.linux arm libraries in the NuGet ecosystem. The issue involves microsoft security advisory cve-2025-21171 | .net remote code execution vulnerability. Remediation is available by upgrading affected packages to version 9.0.1.
CVE-2025-21171 at a Glance
Security Impact
CVSS: 8.1
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).
How to Fix CVE-2025-21171
To remediate this vulnerability, upgrade all affected Microsoft.NetCore.App.Runtime.linux arm dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade Microsoft.NetCore.App.Runtime.linux-arm to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.linux-arm64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.linux-musl-arm to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.linux-musl-arm64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.linux-musl-x64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.linux-x64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.osx-arm64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.osx-x64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.win-arm to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.win-arm64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.win-x64 to 9.0.1
Upgrade Microsoft.NetCore.App.Runtime.win-x86 to 9.0.1
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for Microsoft.NetCore.App.Runtime.linux-arm
How to Check if You Are Affected
To determine whether your application is affected by CVE-2025-21171, inspect your project dependencies for Microsoft.NetCore.App.Runtime.linux arm:
inspect dependencies for Microsoft.NetCore.App.Runtime.linux-arm
Analyze the terminal output to locate any version of Microsoft.NetCore.App.Runtime.linux arm in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 9.0.1), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-122: Heap-based Buffer Overflow, where a heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). In Microsoft.NetCore.App.Runtime.linux arm, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2025-21171 Affected Microsoft.NetCore.App.Runtime.linux arm Versions
12 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
Microsoft.NetCore.App.Runtime.linux-arm
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.linux-arm64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.linux-musl-arm
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.linux-musl-arm64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.linux-musl-x64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.linux-x64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.osx-arm64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.osx-x64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.win-arm
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.win-arm64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.win-x64
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
|
Microsoft.NetCore.App.Runtime.win-x86
|
NuGet |
≥ 9.0.0
< 9.0.1
|
9.0.1
|
References
Frequently Asked Questions
What is CVE-2025-21171?
Which Microsoft.NetCore.App.Runtime.linux arm versions are affected?
What version fixes CVE-2025-21171?
Is Microsoft.NetCore.App.Runtime.linux-arm affected?
Is Microsoft.NetCore.App.Runtime.linux-arm64 affected?
What is the CVSS score of CVE-2025-21171?
What CWE is associated with CVE-2025-21171?
How can I check NuGet dependencies for CVE-2025-21171?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-p54p-p3qm-8vgj",
"modified" : "2025-01-14T19:43:16Z",
"published" : "2025-01-14T19:43:16Z",
"aliases" : [ "CVE-2025-21171" ],
"summary" : "Microsoft Security Advisory CVE-2025-21171 | .NET Remote Code Execution Vulnerability",
"details" : "# Microsoft Security Advisory CVE-2025-21171 | .NET Remote Code Execution Vulnerability\n\n## <a name=\"executive-summary\"></a>Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in .NET 9.0. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nAn attacker could exploit this vulnerability by sending a specially crafted request to the vulnerable web server.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/runtime/issues/111423\n\n## <a name=\"mitigation-factors\"></a>Mitigation factors\n\nMicrosoft has not identified any mitigating factors for this vulnerability.\n\n## <a name=\"affected-software\"></a>Affected software\n\n* Any .NET 9.0 application running on .NET 9.0.0 or earlier.\n\n## <a name=\"affected-packages\"></a>Affected Packages\n\nThe vulnerability affects any Microsoft .NET project if it uses any of affected packages versions listed below\n\n### <a name=\".NET 9\"></a>.NET 9\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\n[Microsoft.NetCore.App.Runtime.linux-arm](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-arm) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.linux-arm64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-arm64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.linux-musl-arm](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-musl-arm) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.linux-musl-arm64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-musl-arm64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.linux-musl-x64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-musl-x64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.linux-x64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.linux-x64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.osx-arm64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.osx-arm64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.osx-x64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.osx-x64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.win-arm](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.win-arm) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.win-arm64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.win-arm64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.win-x64](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.win-x64) | >= 9.0.0, < 9.0.1 | 9.0.1\n[Microsoft.NetCore.App.Runtime.win-x86](https://www.nuget.org/packages/Microsoft.NetCore.App.Runtime.win-x86) | >= 9.0.0, < 9.0.1 | 9.0.1\n\n## Advisory FAQ\n\n### <a name=\"how-affected\"></a>How do I know if I am affected?\n\nIf you have a runtime or SDK with a version listed, or an affected package listed in [affected software](#affected-packages) or [affected packages](#affected-software), you're exposed to the vulnerability.\n\n### <a name=\"how-fix\"></a>How do I fix the issue?\n\n1. To fix the issue please install the latest version of .NET 9.0. If you have installed one or more .NET SDKs through Visual Studio, Visual Studio will prompt you to update Visual Studio, which will also update your .NET SDKs.\n2. If your application references the vulnerable package, update the package reference to the patched version.\n\n* You can list the versions you have installed by running the `dotnet --info` command. You will see output like the following;\n\n```\n.NET SDK:\n Version: 9.0.100\n Commit: 59db016f11\n Workload version: 9.0.100-manifests.3068a692\n MSBuild version: 17.12.7+5b8665660\n\nRuntime Environment:\n OS Name: Mac OS X\n OS Version: 15.2\n OS Platform: Darwin\n RID: osx-arm64\n Base Path: /usr/local/share/dotnet/sdk/9.0.100/\n\n.NET workloads installed:\nThere are no installed workloads to display.\nConfigured to use loose manifests when installing new manifests.\n\nHost:\n Version: 9.0.0\n Architecture: arm64\n Commit: 9d5a6a9aa4\n\n.NET SDKs installed:\n 9.0.100 [/usr/local/share/dotnet/sdk]\n\n.NET runtimes installed:\n Microsoft.AspNetCore.App 9.0.0 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]\n Microsoft.NETCore.App 9.0.0 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]\n\nOther architectures found:\n x64 [/usr/local/share/dotnet]\n registered at [/etc/dotnet/install_location_x64]\n\nEnvironment variables:\n Not set\n\nglobal.json file:\n Not found\n\nLearn more:\n https://aka.ms/dotnet/info\n\nDownload .NET:\n https://aka.ms/dotnet/download\n```\n\n* If you're using .NET 9.0, you should download and install .NET 9.0 Runtime or .NET 9.0.100 SDK (for Visual Studio 2022 v17.12 latest Preview) from https://dotnet.microsoft.com/download/dotnet-core/9.0.\n\nOnce you have installed the updated runtime or SDK, restart your apps for the update to take effect.\n\nAdditionally, 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.\n\n## Other Information\n\n### Reporting Security Issues\n\nIf you have found a potential security issue in .NET 9.0 please email details to secure@microsoft.com. Reports may qualify for the Microsoft .NET Core & .NET 5 Bounty. Details of the Microsoft .NET Bounty Program including terms and conditions are at <https://aka.ms/corebounty>.\n\n### Support\n\nYou can ask questions about this issue on GitHub in the .NET GitHub organization. The main repos are located at https://github.com/dotnet/runtime. The Announcements repo (https://github.com/dotnet/Announcements) will contain this bulletin as an issue and will include a link to a discussion issue. You can ask questions in the linked discussion issue.\n\n### Disclaimer\n\nThe information provided in this advisory is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.\n\n### External Links\n\n[CVE-2025-21171]( https://www.cve.org/CVERecord?id=CVE-2025-21171)\n\n### Revisions\n\nV1.0 (January 14, 2024): Advisory published.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.linux-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.linux-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.linux-musl-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.linux-musl-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.linux-musl-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.linux-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.osx-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.osx-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.win-arm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.win-arm64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.win-x64"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "NuGet",
"name" : "Microsoft.NetCore.App.Runtime.win-x86"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.0.1"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/dotnet/runtime/security/advisories/GHSA-p54p-p3qm-8vgj"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-21171"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/dotnet/runtime"
}, {
"type" : "WEB",
"url" : "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21171"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-122" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2025-01-14T19:43:16Z",
"nvd_published_at" : "2025-01-14T18:15:30Z"
}
}