The Update BureauKB5045933: Cumulative update for .NET Framework, versions 3.5 and 4.8.1, on Windows 10 21H2/22H2, November 2024. ASP.NET compilation and CLR reliability issues addressed
.NET Framework's ASP.NET design-time compilation error and several CLR and user-group lookup issues are addressed. Windows Update for Business receives these changes in its next security update, not through this release.
Does it affect you? Applies to: Devices running Windows 10, version 21H2 or 22H2, with .NET Framework 3.5 or 4.8.1 installed. The available packages include Windows 10 Enterprise LTSC 2021.
What changes
Fixes 7 changes
ASP.NET
For: Visual Studio users
-
The design-time compilation issue that produces a “The type initializer for ‘System.Web.UI.Util’ threw an exception.” error is addressed.1
Applies to Visual Studio design-time compilation in .NET Framework ASP.NET projects.
CLR
- A rare case where a thread entering the CLR for the first time could cause an infinite loop is addressed.2
- An issue with interface call devirtualization when JIT optimizations are enabled is addressed.3
- An issue with a security feature bypass when using SecUtility.RandomByte is addressed.4
- An information disclosure issue involving the performance counter is addressed.5
- An issue that could cause out-of-memory exceptions during garbage collection is addressed for applications running under job limits.6
.NET Fundamentals
For: .NET application developers
- An issue retrieving a particular user's group membership with UserPrincipal.GetAuthorizationGroups is addressed.7
Technical details
Data sheet · Security · Downloads · Components Click to collapse or expand
Data sheet
- Released
- 2024-11-12
- Classification
- Updates
- Type
- Cumulative update
- Restart
- Required
- Replaces
- KB5042097
- Replaced by
- KB5049621
| Version | File version | Channel |
|---|---|---|
| 3.5 | 2.0.50727.9179 | General availability |
| 4.8.1 | 4.8.9282.0 | General availability |
Security
No vulnerabilities are listed for this update.
Downloads (Microsoft Update Catalog)
Updated components
55 files changed since the previous update for the same versions.
| Top changed components | Files |
|---|---|
| .NET runtime (CLR) | 18 |
| ASP.NET | 15 |
Verified in package: changed files confirm ASP.NET.
Sources
Cited passages from Microsoft's official notes (7)
-
1.
Addresses an issue where "The type initializer for ‘System.Web.UI.Util’ threw an exception." error with design-time compilation in Visual Studio for .NET Framework ASP.Net projects.
support.microsoft.com -
2.
Address an issue where in rare cases where an infinite loop could occur when a thread enters CLR for the first time.
support.microsoft.com -
3.
Address an issue in cases where incorrect interface call devirtualization could occur when JIT optimizations are enabled.
support.microsoft.com -
4.
Addresses an issue with a security feature bypass vulnerability when using SecUtility.RandomByte.
support.microsoft.com -
5.
Addresses an issue with information disclosure with the performance counter.
support.microsoft.com -
6.
Addresses an issue with out of memory exceptions during garbage collection while running applications running under job limits.
support.microsoft.com -
7.
Addresses an issue with .NET API UserPrincipal.GetAuthorizationGroups to retrieve the Membership of a particular user.
support.microsoft.com
Checked automatically: 8 of 8 checks passed, 7 quoted passages · compared with Microsoft's page on Oct 20, 2026
- Quotes found in the official pages: passed
- Numbers found in the sources: passed
- Vulnerabilities from the dossier only: passed
- Links to allowed domains only: passed
- Every official change covered: passed
- Readable plain text: passed
- Changes confirmed by the file list: passed
- Sources agree: passed
A second AI read the text against the sources: correctness 5/5, clarity 3/5, completeness 4/5. How we work
Published by The Update Bureau. Written with AI from Microsoft's own documents, checked by rules and a second AI. How we work · Report a mistake