GHSA-63gh-g2x5-x69v: Buffer Overflow
Microsoft Security Advisory CVE-2026-71328 – .NET and Visual Studio Remote Code Execution Vulnerability
Executive summary
Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.DiaSymReader.Native. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
Microsoft.DiaSymReader.Native can perform an out of bounds write while processing MSFZ PDB files.
Announcement
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/440
CVSS Details
- Version: 3.1 - Severity: High - Score: 8.8 - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness: CWE-122 (Heap-based Buffer Overflow)
Affected Platforms
- Platforms: Windows - Architectures: All
<a name="affected-packages"></a>Affected Packages The vulnerability affects any Microsoft .NET project if it uses any of affected package versions listed below
<a name=".NET 11 RC1"></a>.NET 11 RC1 Package name | Affected version | Patched version ------------ | ---------------- | ------------------------- Microsoft.DiaSymReader.Native | >= 17.10.0-beta1.24272.1, <= 18.9.0-beta1.26405.1 | 18.9.0-beta1.26405.2
<a name=".NET 10"></a>.NET 10 Package name | Affected version | Patched version ------------ | ---------------- | ------------------------- Microsoft.DiaSymReader.Native | >= 17.12.0-beta1.24603.5, <= 18.9.0-beta1.26405.1 | 18.9.0-beta1.26405.2
<a name=".NET 9"></a>.NET 9 Package name | Affected version | Patched version ------------ | ---------------- | ------------------------- Microsoft.DiaSymReader.Native | >= 17.12.0-beta1.24603.5, <= 18.9.0-beta1.26405.1 | 18.9.0-beta1.26405.2
<a name=".NET 8"></a>.NET 8 Package name | Affected version | Patched version ------------ | ---------------- | ------------------------- Microsoft.DiaSymReader.Native | >= 17.12.0-beta1.24603.5, <= 18.9.0-beta1.26405.1 | 18.9.0-beta1.26405.2
Advisory FAQ
<a name="how-affected"></a>How do I know if I am affected?
If using a package listed in affected packages, a project is 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 or Visual Studio. 2. If a developer's application references Microsoft.DiaSymReader.Native, update the package reference to version 18.9.0-beta1.26405.2 or later.
Once developers have installed the updated runtime, SDK, Visual Studio, or package, they should restart their apps in order for the update to take effect.
Other Information
Reporting Security Issues
If users 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. Further information can be found in the MSRC Report an Issue FAQ.
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
Users 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. Users 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-2026-71328
Acknowledgements
41ae55e9310ff27fa6f26af4727e5590
Revisions
V1.0 (09/08/2026): Advisory published.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
nuget/Microsoft.DiaSymReader.Nativeto a version that resolves this vulnerability.Fixed in 18.9.0-beta1.26405.2 - Upgrade
Upgrade
Microsoft.DiaSymReader.Nativeto a version that resolves this vulnerability.Fixed in 18.9.0-beta1.26405.2 - Operational
After updating to the patched runtime, SDK, Visual Studio, or Microsoft.DiaSymReader.Native package, restart your apps so the update takes effect.
Event History
Frequently Asked Questions
Which environments are in scope?
The advisory identifies Windows systems on all architectures. A .NET project is affected only if it uses an affected version of the Microsoft.DiaSymReader.Native NuGet package.
What would exploitation require?
The vulnerable component must process an MSFZ PDB file. The CVSS vector indicates network-based attack conditions with no privileges required, but user interaction is required.
What should teams do to remediate the issue?
Update applications so they no longer use an affected Microsoft.DiaSymReader.Native package version, using the advisory’s patched-version guidance. The advisory specifically directs developers to update their applications to remove the vulnerability.
How can I determine whether an application is affected?
Inspect the application’s NuGet dependencies, including transitive dependencies, for Microsoft.DiaSymReader.Native. If the resolved package version is one of the advisory’s affected versions, the application is affected.