MicrosoftKB4601052February 9, 2021-KB4601052 Cumulative Update for .NET Framework 4.8 for Windows 10 Version 1703
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.6 High
AI Score
Confidence
High
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.002 Low
EPSS
Percentile
56.4%
February 9, 2021-KB4601052 Cumulative Update for .NET Framework 4.8 for Windows 10 Version 1703
Release Date:
February 9, 2021Version: .NET Framework 4.8
Summary
| Security ImprovementsThis security update addresses a denial of service vulnerability in .NET Framework. For more information please see CVE-2021-24111.Quality ImprovementsASP.NET | - Addresses an issue where after installing the update released on October 20th, some ASP.Net applications fail during precompilation – likely with a message that contains the words “Error ASPCONFIG.” |
|---|---|
| WPF1 | - Addresses a hang when scrolling to the end of a TreeView, when layout rounding is enabled and DPI scaling is not 100%. |
| CLR | - Improves the reliability of automatic Native Image generation task. |
| 1 Windows Presentation Foundation (WPF) |
Known issues in this update
Symptom| After installing this update, WPF apps may crash with a callstack similar to`
Exception Info: System.NullReferenceException at System.Windows.Interop.HwndMouseInputProvider.HasCustomChrome(System.Windows.Interop.HwndSource, RECT ByRef)
at System.Windows.Interop.HwndMouseInputProvider.GetEffectiveClientRect(IntPtr)
at System.Windows.Interop.HwndMouseInputProvider.PossiblyDeactivate(IntPtr, Boolean)
at System.Windows.Interop.HwndMouseInputProvider.Dispose()
This occurs when disposing an HwndSource whose RootVisual is null, a situation that arises in Visual Studio when docking or splitting windows, and could arise in other apps. ---|--- **Workaround**| To work around this problem, set two AppContext switches using one of the methods described in [AppContext Class (System)](<https://docs.microsoft.com/en-us/dotnet/api/system.appcontext?view=netcore-3.1#remarks>) under the heading “AppContext for library consumers”. The switches are named**Switch.System.Windows.Interop.MouseInput.OptOutOfMoveToChromedWindowFix**and**Switch.System.Windows.Interop.MouseInput.DoNotOptOutOfMoveToChromedWindowFix** and both should be set to “true”. The first switch avoids the crash, but re-introduces the bug fixed in the KBs. The second switch is currently ignored, but will be recognized in a future .NET update that contains a fix for the null-reference crash; it restores the original bug fix.For example, using the app.config file method to apply the workaround at application scope:
<AppContextSwitchOverrides value="Switch.System.Windows.Interop.MouseInput.OptOutOfMoveToChromedWindowFix=true; Switch.System.Windows.Interop.MouseInput.DoNotOptOutOfMoveToChromedWindowFix=true " />
`
How to get this update
| Install this update****Release Channel | Available | Next Step |
|---|---|---|
| Windows Update and Microsoft Update | Yes | None. This update will be downloaded and installed automatically from Windows Update. |
| Microsoft Update Catalog | Yes | To get the standalone package for this update, go to the Microsoft Update Catalog website. |
| Windows Server Update Services (WSUS) | Yes | This update will automatically sync with WSUS if you configure Products and Classifications as follows:Product: Windows 10 Version 1703Classification: Security Updates File informationFor a list of the files that are provided in this update, download the file information for cumulative update. |
Information about protection and security
- Protect yourself online: Windows Security support
- Learn how we guard against cyber threats: Microsoft Security
Related
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.6 High
AI Score
Confidence
High
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.002 Low
EPSS
Percentile
56.4%