Microsoft Security Advisory CVE-2026-35433 – .NET Elevation of Privilege Vulnerability
Date: 2026-05
Affected: nuget/Microsoft.WindowsDesktop.App.Runtime.win-x86, nuget/Microsoft.WindowsDesktop.App.Runtime.win-x64, nuget/Microsoft.WindowsDesktop.App.Runtime.win-arm64
Attack vector: other
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2026-35433
CWE: CWE-122
CWE-20
CVSS: 7.3 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L)

## Executive Summary: Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 8.0, .NET 9.0, and .NET 10.0. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally. ## Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/398 ## CVSS Details - **Version:** 3.1 - **Severity:** High - **Score:** 7.3 - **Vector:** AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L/E:U/RL:O/RC:C - **Weakness:** CWE-122: Heap-based Buffer Overflow, CWE-20: Improper Input Validation ## 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 10"></a>.NET 10 Package name | Affected version | Patched version ------------ | ---------------- | ------------------------- [Microsoft.WindowsDesktop.App.Runtime.win-arm64](https://www.nuget.org/packages/Microsoft.WindowsDesktop.App.Runtime.win-arm64) | >= 10.0.0, <= 10.0.7 | 10.0.8 [Microsoft.WindowsDesktop.App.Runtime.win-x64](https://www.nuget.org/packages/Microsoft.WindowsDesktop.App.Runtime.win-x64) | >= 10.0.0, <= 10.0.7 | 10.0.8 [Microsoft.WindowsDesktop.App.Runtime.win-x86](https://


Mitigations:

Architectural layers (MAESTRO):