CVE-2026-70354

## Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in Windows Presentation Foundation. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. An out-of-bounds write in .NET allows an unauthorized attacker to execute code locally. ## Announcement Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/432 ## CVSS Details - **Version:** 3.1 - **Severity:** High - **Score:** 7.8 - **Vector:** `CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C` - **Weakness:** CWE-787: Out-of-bounds Write ## 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, <= 10.0.10 | 10.0.11 [Microsoft.WindowsDesktop.App.Runtime.win-x64](https://www.nuget.org/packages/Microsoft.WindowsDesktop.App.Runtime.win-x64) | >= 10.0.0, <= 10.0.10 | 10.0.11 [Microsoft.WindowsDesktop.App.Runtime.win-x86](https://www.nuget.org/packages/Microsoft.WindowsDesktop.App.Runtime.win-x86) | >= 10.0.0, <= 10.0.10 | 10.0.11 ### <a name=".NET 9"></a>.NET 9 Package name | Affected version | Patched version ------------ | ---------------- | ------------------------- [Microsoft.WindowsDesktop.App.Runtime.win-arm64](https://www.nuget.org/packages/Microsoft.WindowsDesktop.App.Runtime.win-arm64) | >= 9.0.0, <= 9.0.18 | 9.0.19 [Microsoft.WindowsDesktop.App.Runtime.win-x64](https://www.nuget.org/packages/Microsoft.WindowsDesktop.App.Runtime.win-x64) | >= 9.0.0, <= 9.0.18 | 9.0.19 [Microsoft.Win