Windows Server · 2025 · Release · Security update (Patch Tuesday)
August 12, 2025—KB5063878 (OS Build 26100.4946)
- Release
- Cumulative update
- KB5063878 — Microsoft's article, opens in a new tab
Windows Server 2025: Current LTSC release
Microsoft's known issues — KB5063878
- Issue Known issue A security improvement was included in the August 2025 Windows security update and later updates to enforce the requirement that User Account Control (UAC) prompt for administrator credentials when performing Windows Installer (MSI) repair and related operations. This improvement addressed security vulnerability CVE-2025-50173 . After installing the update, standard users might see a User Account Control (UAC) prompt in several scenarios. Running MSI repair commands (such as msiexec /fu ). Opening Autodesk apps, including some versions of AutoCAD, Civil 3D and Inventor CAM, or when installing an MSI file after a user signs into the app for the first time. Installing apps that configure per u Workaround: This issue is addressed in KB5065426 . This issue is addressed KB5068861 .
Known issues — reported on the forum
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