Vulnerabilities in pkg:nuget/Microsoft.Native.Quic.MsQuic.Schannel

PACKAGE
Advisory Identifier: GHSA-2mxg-prvg-9jfg
Advisory Summary

CVE-2026-85790 is a MODERATE (CVSS 5.9) microsoft security advisory cve-2026-85790 - vulnerability (CWE-416: Use After Free) affecting Microsoft.Native.Quic.MsQuic.Schannel libraries in the NuGet ecosystem. The issue involves microsoft security advisory cve-2026-85790 - .net information disclosure vulnerability. Remediation is available by upgrading affected packages to version 2.6.2.

7 Known Advisory Record(s)
Package Vulnerability Intelligence

pkg:nuget/Microsoft.Native.Quic.MsQuic.Schannel

7 Known Advisory Record(s)

Vulnerability advisories affecting package pkg:nuget/Microsoft.Native.Quic.MsQuic.Schannel. Select an advisory below to view technical details or fixes.

Advisory ID CVE / NVD Severity Summary
GHSA-2mxg-prvg-9jfg CVE-2026-85790 MODERATE Microsoft Security Advisory CVE-2026-85790 - .NET Information Disclosure Vulnerability
GHSA-5gjq-3f94-rcf7 CVE-2026-105016 CRITICAL Microsoft Security Advisory CVE-2026-105016 - Microsoft QUIC Remote Code Execution Vulnerability
GHSA-92f5-vc22-8j33 CVE-2026-62815 CRITICAL Microsoft QUIC: Remote Code Execution Vulnerability
GHSA-gvvw-8j96-8g5r CVE-2026-32179 CRITICAL MsQuic has a Remote Elevation of Privilege Vulnerability
GHSA-xh5m-8qqp-c5x7 CVE-2023-38171 HIGH Remote Denial of Service Vulnerability in Microsoft.Native.Quic.MsQuic.Schannel
GHSA-fr44-546p-7xcp CVE-2023-36435 HIGH MsQuic Remote Denial of Service Vulnerability
GHSA-2x7m-gf85-3745 - HIGH Remote Denial of Service Vulnerability in Microsoft QUIC

CVE-2026-85790 at a Glance

CVE Identifier CVE-2026-85790
GHSA Identifier GHSA-2mxg-prvg-9jfg
Severity MODERATE
CVSS v3.1 Base Score 5.9
CWE Classification CWE-416: Use After Free
Affected Product Microsoft.Native.Quic.MsQuic.Schannel
Package Ecosystem NuGet
Published Date
Last Updated

Security Impact

CVSS: 5.9

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:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-85790

To remediate this vulnerability, upgrade all affected Microsoft.Native.Quic.MsQuic.Schannel dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

Microsoft.Native.Quic.MsQuic.Schannel fixed: 2.6.2
Upgrade Microsoft.Native.Quic.MsQuic.Schannel to 2.6.2
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for Microsoft.Native.Quic.MsQuic.Schannel

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-85790, inspect your project dependencies for Microsoft.Native.Quic.MsQuic.Schannel:

inspect dependencies for Microsoft.Native.Quic.MsQuic.Schannel

Analyze the terminal output to locate any version of Microsoft.Native.Quic.MsQuic.Schannel in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.6.2), 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-416: Use After Free, where the 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. In Microsoft.Native.Quic.MsQuic.Schannel, 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

## Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.Native.Quic.MsQuic.Schannel. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. Various vulnerabilities in MsQuic are addressed by an updated native-binary dependency update. ## Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/470 ## CVSS Details - **Version:** 3.1 - **Severity:** Moderate - **Score:** 5.9 - **Vector:** `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N` - **Weakness:** CWE-416 (Use After Free) ## Affected Platforms - **Platforms:** Windows - **Architectures:** All ## <a name="affected-packages"></a>Affected Packages The vulnerability affects Microsoft .NET projects that use an affected package version listed below. Package name | Affected version | Patched version ------------ | ---------------- | --------------- [Microsoft.Native.Quic.MsQuic.Schannel](https://www.nuget.org/packages/Microsoft.Native.Quic.MsQuic.Schannel) | >= 1.9.0, <= 2.6.1 | 2.6.2 ## Advisory FAQ ### <a name="how-affected"></a>How do I know if I am affected? If using a package listed in [affected packages](#affected-packages), you're exposed to the vulnerability. ### <a name="how-fix"></a>How do I fix the issue? 1. To fix the issue please install the latest version of .NET. 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. 2. If your application references the vulnerable package, update the package reference to the patched version. You can list the versions you have installed by running the `dotnet --info` command. Once you have installed the updated runtime or SDK, restart your apps for the update to take effect. 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. ## Other Information ### Reporting Security Issues If you have found a potential security issue in a supported version of .NET, please report it to the Microsoft Security Response Center (MSRC) via the [MSRC Researcher Portal](https://msrc.microsoft.com/report/vulnerability/new). Further information can be found in the MSRC [Report an Issue FAQ](https://www.microsoft.com/msrc/faqs-report-an-issue). Security reports made through MSRC may qualify for the Microsoft .NET Bounty. Details of the Microsoft .NET Bounty Program including terms and conditions are at https://aka.ms/corebounty. ### Support You 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. ### Disclaimer The 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. ### External Links [CVE-2026-85790](https://www.cve.org/CVERecord?id=CVE-2026-85790) ### Acknowledgements - reinusKR ### Revisions V1.0 (10/13/2026): Advisory published.

CVE-2026-85790 Affected Microsoft.Native.Quic.MsQuic.Schannel Versions

1 component(s)
Fixed Versions:
2.6.2
Product / Package Ecosystem Affected Versions Fixed Version
Microsoft.Native.Quic.MsQuic.Schannel
NuGet
≥ 1.9.0
< 2.6.2
2.6.2

References

Frequently Asked Questions

What is CVE-2026-85790?
CVE-2026-85790 is a security vulnerability in Microsoft.Native.Quic.MsQuic.Schannel involving Microsoft Security Advisory CVE-2026-85790 - .NET Information Disclosure Vulnerability under CWE-416: Use After Free.
Which Microsoft.Native.Quic.MsQuic.Schannel versions are affected?
Affected versions include releases prior to 2.6.2 across affected packages: Microsoft.Native.Quic.MsQuic.Schannel.
What version fixes CVE-2026-85790?
Upgrading to 2.6.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is Microsoft.Native.Quic.MsQuic.Schannel affected?
Yes, Microsoft.Native.Quic.MsQuic.Schannel is affected in releases prior to 2.6.2. Upgrade your dependency to 2.6.2 or later.
What is the CVSS score of CVE-2026-85790?
CVE-2026-85790 has a CVSS v3.1 base score of 5.9 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-85790?
CVE-2026-85790 is classified under CWE-416: Use After Free (The 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.).
How can I check NuGet dependencies for CVE-2026-85790?
Run the dependency tree command: 'inspect dependencies for Microsoft.Native.Quic.MsQuic.Schannel'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-2mxg-prvg-9jfg",
  "modified" : "2026-10-13T20:42:44Z",
  "published" : "2026-10-13T20:42:44Z",
  "aliases" : [ "CVE-2026-85790" ],
  "summary" : "Microsoft Security Advisory CVE-2026-85790 - .NET Information Disclosure Vulnerability",
  "details" : "## Executive summary\n\nMicrosoft is releasing this security advisory to provide information about a vulnerability in Microsoft.Native.Quic.MsQuic.Schannel. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.\n\nVarious vulnerabilities in MsQuic are addressed by an updated native-binary dependency update.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/470\n\n## CVSS Details\n\n- **Version:** 3.1\n- **Severity:** Moderate\n- **Score:** 5.9\n- **Vector:** `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N`\n\n- **Weakness:** CWE-416 (Use After Free)\n## Affected Platforms\n\n- **Platforms:** Windows\n- **Architectures:** All\n\n## <a name=\"affected-packages\"></a>Affected Packages\n\nThe vulnerability affects Microsoft .NET projects that use an affected package version listed below.\n\nPackage name | Affected version | Patched version\n------------ | ---------------- | ---------------\n[Microsoft.Native.Quic.MsQuic.Schannel](https://www.nuget.org/packages/Microsoft.Native.Quic.MsQuic.Schannel) | >= 1.9.0, <= 2.6.1 | 2.6.2\n\n## Advisory FAQ\n\n### <a name=\"how-affected\"></a>How do I know if I am affected?\n\nIf using a package listed in [affected packages](#affected-packages), 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. 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. You can list the versions you have installed by running the `dotnet --info` command.\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 a supported version of .NET, please report it to the Microsoft Security Response Center (MSRC) via the [MSRC Researcher Portal](https://msrc.microsoft.com/report/vulnerability/new). Further information can be found in the MSRC [Report an Issue FAQ](https://www.microsoft.com/msrc/faqs-report-an-issue).\n\nSecurity reports made through MSRC may qualify for the Microsoft .NET 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-2026-85790](https://www.cve.org/CVERecord?id=CVE-2026-85790)\n\n### Acknowledgements\n\n- reinusKR\n\n### Revisions\n\nV1.0 (10/13/2026): Advisory published.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
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  "references" : [ {
    "type" : "WEB",
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  }, {
    "type" : "WEB",
    "url" : "https://github.com/dotnet/announcements/issues/470"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/dotnet/runtime/issues/135704"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/dotnet/runtime"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-416" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-10-13T20:42:44Z",
    "nvd_published_at" : null
  }
}