Update Details
2025-10 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for arm64 (KB5066133)
Last Modified:
10/14/2025
Size:
89.3 MB
UpdateID:
49dbb4fe-f1fe-4aab-b84f-e6e66075284d
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Details:
Overview
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Package Details
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Description:
A security issue has been identified in a Microsoft software product that could affect your system. You can help protect your system by installing this update from Microsoft. For a complete listing of the issues that are included in this update, see the associated Microsoft Knowledge Base article. After you install this update, you may have to restart your system.
Architecture:
n/a
Classification:
Security Updates
Supported products:
Windows 11
Supported languages:
all
MSRC Number:
n/a
MSRC severity:
Critical
KB article numbers:
5066133
More information:
https://support.microsoft.com/help/5066133
Support Url:
https://support.microsoft.com/help/5066133
This update has been replaced by the following updates:
2026-05 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for arm64 (KB5087058)
2026-04 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for arm64 (KB5082424)
This update replaces the following updates:
2025-07 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for arm64 (KB5056580)
2025-01 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for ARM64 (KB5049624)
2025-09 Cumulative Update for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for arm64 (KB5064403)
2025-08 Cumulative Update Preview for .NET Framework 3.5 and 4.8.1 for Windows 11, version 23H2 for arm64 (KB5064403)
There are no additional languages to select
Restart behavior:
Can request restart
May request user input:
No
Must be installed exclusively:
Requires network connectivity:
No
Uninstall Notes:
n/a
Uninstall Steps:
n/a
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