Microsoft Security Advisory CVE-2026-96234 - .NET and Visual Studio Information Disclosure Vulnerability

Executive Summary

Microsoft has issued a security advisory regarding a vulnerability in Microsoft.WindowsDesktop.App.Runtime (WPF). This advisory outlines steps developers can take to update their applications and eliminate this vulnerability.

Restrictive XAML and XPS security fixes prevent unsafe URI fetching and navigation, propagate untrusted-input states across hyperlink navigation, introduce TrueType font protection along with XAML nesting-depth limits, and avoid caching positive DNS zone-policy decisions.

Announcement

The official announcement for this issue is available at https://github.com/dotnet/announcements/issues/482

CVSS Details

• Version: 3.1
• Severity: Moderate
• Score: 5.3
• Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
• Weakness: CWE-346 (Origin Validation Error)

Affected Platforms

• Platforms: Windows
• Architectures: All

Affected Packages

This vulnerability impacts Microsoft .NET projects utilizing any of the affected package versions listed below:

Advisory FAQ

How do I know if I am affected?

If your project relies on any package listed in the Affected Packages section, your application is exposed to this vulnerability.

How do I fix the issue?

1. Install the latest version of .NET. If you installed one or more .NET SDKs through Visual Studio, Visual Studio will prompt you to update, which also updates your .NET SDKs.
2. If your application references a vulnerable package, update that reference to the patched version. You can check installed versions using the dotnet --info command.

After installing the updated runtime or SDK, restart your applications for the update to take effect.

Furthermore, if you have deployed self-contained applications targeting any affected version, they remain vulnerable until recompiled and redeployed.

Other Information

Reporting Security Issues

If you discover a potential security vulnerability in a supported version of .NET, please report it to the Microsoft Security Response Center (MSRC) using the MSRC Researcher Portal. Additional details can be found in the MSRC Report an Issue FAQ.

Security submissions through MSRC may qualify for the Microsoft .NET Bounty. Details, terms, and conditions of the Microsoft .NET Bounty Program can be found at https://aka.ms/corebounty.

Support

You can ask questions about this issue within the .NET GitHub organization. The primary repositories are located at https://github.com/dotnet/runtime. The Announcements repository (https://github.com/dotnet/Announcements) contains this bulletin as an issue with a link to a dedicated discussion issue where inquiries may be submitted.

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-2026-96234

Acknowledgements

• nono
• piropatriot
• Ali Az
• Anonymous
• kayiz with Lien Phat Technology Corporation
• Muhammad Abdul Rehman
• Ky0toFu (@ky0tofu)

Revisions

V1.0 (10/13/2026): Advisory published.