Microsoft Security Advisory CVE-2026-87697 - .NET and Visual Studio Remote Code Execution Vulnerability
The source advisory has changed since this explanation was prepared. Check the current technical data and original advisory below.
Executive Summary
Microsoft has issued a security advisory regarding a vulnerability in Microsoft.WindowsDesktop.App.Runtime (WPF). This guidance describes the issue and the steps developers should take to update their applications.
WPF XPS synthetic hyperlinks exposed through UI Automation can bypass restrictive navigation checks and access attacker-controlled content, allowing remote code execution following user interaction.
Announcement
The official announcement for this issue is available at https://github.com/dotnet/announcements/issues/471
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-502 (Deserialization of Untrusted Data)
Affected Platforms
- Platforms: Windows
- Architectures: All
Affected Packages
This vulnerability impacts Microsoft .NET projects utilizing any of the affected package versions listed below:
| Package name | Affected version | Patched version |
|---|---|---|
| Microsoft.WindowsDesktop.App.Runtime.win-arm64 | >= 9.0.0, <= 9.0.20 | 9.0.21 |
| Microsoft.WindowsDesktop.App.Runtime.win-x64 | >= 9.0.0, <= 9.0.20 | 9.0.21 |
| Microsoft.WindowsDesktop.App.Runtime.win-x86 | >= 9.0.0, <= 9.0.20 | 9.0.21 |
| Microsoft.WindowsDesktop.App.Runtime.win-arm64 | >= 8.0.0, <= 8.0.31 | 8.0.32 |
| Microsoft.WindowsDesktop.App.Runtime.win-x64 | >= 8.0.0, <= 8.0.31 | 8.0.32 |
| Microsoft.WindowsDesktop.App.Runtime.win-x86 | >= 8.0.0, <= 8.0.31 | 8.0.32 |
| Microsoft.WindowsDesktop.App.Runtime.win-arm64 | >= 11.0.0-preview.1, <= 11.0.0-rc.1 | 11.0.0-rc.2 |
| Microsoft.WindowsDesktop.App.Runtime.win-x64 | >= 11.0.0-preview.1, <= 11.0.0-rc.1 | 11.0.0-rc.2 |
| Microsoft.WindowsDesktop.App.Runtime.win-x86 | >= 11.0.0-preview.1, <= 11.0.0-rc.1 | 11.0.0-rc.2 |
| Microsoft.WindowsDesktop.App.Runtime.win-arm64 | >= 10.0.0, <= 10.0.12 | 10.0.13 |
| Microsoft.WindowsDesktop.App.Runtime.win-x64 | >= 10.0.0, <= 10.0.12 | 10.0.13 |
| Microsoft.WindowsDesktop.App.Runtime.win-x86 | >= 10.0.0, <= 10.0.12 | 10.0.13 |
Advisory FAQ
How do I know if I am affected?
If your project utilizes any of the packages listed in the Affected Packages table, your application is exposed to this vulnerability.
How do I fix the issue?
- Install the latest version of .NET. If one or more .NET SDKs were installed through Visual Studio, Visual Studio will prompt you to update, which updates the .NET SDKs as well.
- If your application references a vulnerable package, update that package reference to the patched version. You can check installed versions with the
dotnet --infocommand.
After installing the updated runtime or SDK, restart applications for changes to take effect.
In addition, self-contained applications built against any affected version must be recompiled and redeployed.
Other Information
Reporting Security Issues
To report a potential security issue in a supported version of .NET, contact the Microsoft Security Response Center (MSRC) via the MSRC Researcher Portal. Additional details are available in the MSRC Report an Issue FAQ.
Qualifying reports submitted through MSRC may be eligible for the Microsoft .NET Bounty. Details and terms are available at https://aka.ms/corebounty.
Support
Questions regarding this issue can be asked within the .NET GitHub organization. The main repositories are located at https://github.com/dotnet/runtime. The Announcements repository (https://github.com/dotnet/Announcements) includes this bulletin as an issue with a link to a discussion thread.
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
Acknowledgements
- 41ae55e9310ff27fa6f26af4727e5590
Revisions
V1.0 (10/13/2026): Advisory published.
What to do
To resolve this vulnerability:
- Install the latest version of .NET. If .NET SDKs were installed via Visual Studio, accept the Visual Studio prompt to update, which updates the SDKs concurrently.
- Update vulnerable package references in your applications to the appropriate patched release. Installed package versions can be verified using the
dotnet --infocommand.
Restart running applications after updating the runtime or SDK.
If you have deployed self-contained applications targeting affected runtime versions, recompile and redeploy those applications.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| .NET (NuGet) | Microsoft.WindowsDesktop.App.Runtime.win-arm64 | >= 9.0.0, < 9.0.21, >= 8.0.0, < 8.0.32, >= 11.0.0-preview.1, < 11.0.0-rc.2, >= 10.0.0, < 10.0.13 | 9.0.21, 8.0.32, 11.0.0-rc.2, 10.0.13 |
| .NET (NuGet) | Microsoft.WindowsDesktop.App.Runtime.win-x64 | >= 9.0.0, < 9.0.21, >= 8.0.0, < 8.0.32, >= 11.0.0-preview.1, < 11.0.0-rc.2, >= 10.0.0, < 10.0.13 | 9.0.21, 8.0.32, 11.0.0-rc.2, 10.0.13 |
| .NET (NuGet) | Microsoft.WindowsDesktop.App.Runtime.win-x86 | >= 9.0.0, < 9.0.21, >= 8.0.0, < 8.0.32, >= 11.0.0-preview.1, < 11.0.0-rc.2, >= 10.0.0, < 10.0.13 | 9.0.21, 8.0.32, 11.0.0-rc.2, 10.0.13 |
References
- https://github.com/dotnet/wpf/security/advisories/GHSA-c27m-942f-rcfh
- https://github.com/dotnet/announcements/issues/471
- https://github.com/dotnet/wpf/issues/12021
- https://github.com/dotnet/wpf
- https://nvd.nist.gov/vuln/detail/CVE-2026-87697
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87697
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H- Weakness (CWE)
CWE-502- Platform
- .NET (NuGet)
- Package
Microsoft.WindowsDesktop.App.Runtime.win-arm64, Microsoft.WindowsDesktop.App.Runtime.win-x64, Microsoft.WindowsDesktop.App.Runtime.win-x86- Disclosed
- 13.10.2026
- Updated
- 19.10.2026 22:17
Sources and licenses · Edited or translated by DockRay; source rights and applicable licenses are retained.
OSV / GitHub Advisory Database - GHSA-c27m-942f-rcfh - CC BY 4.0
Vulnerability history: Microsoft.WindowsDesktop.App.Runtime.win-arm64
All published vulnerabilities of this package (.NET (NuGet)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 19
- First → latest
- 12.2022 10.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- High 16
- Medium 3
Disclosures per year
- 2022: 1
- 2023: 2
- 2024: 1
- 2025: 0
- 2026: 15
-
Microsoft Security Advisory CVE-2026-87697 - .NET and Visual Studio Remote Code Execution Vulnerability this entry
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