Skip to the content
The Update Bureau
.NET Framework 3.5 / 4.8.1 .NET Framework 3.5 / 4.8.1 Security update
Patch Tuesday

KB5101005

KB5101005: Cumulative update for .NET Framework, versions 3.5 and 4.8.1, on Windows Server 2022, July 2026. Secure web requests and debugger value reports improved

In short

Addresses 17 .NET Framework vulnerabilities and two reliability issues. Some secure web requests could hang, and a debugger could report certain values incorrectly.

Does it affect you? Applies to: Windows Server 2022 devices with .NET Framework 3.5 or 4.8.1 installed.

File version
2.0.50727.9182 · 4.8.9339.0
Security
17 fixed
Restart
Required
Review notes Additional details from the official release notes (1) Read note
  • What changes Microsoft identifies these CVEs as denial-of-service vulnerabilities. The update addresses them, but the official page does not specify that they make an app stop responding.

The official sources are linked at the end of the page.

What changes

Fixes 19 changes

.NET Framework

17 items

For: Windows Server 2022 devices

  • Addresses a flaw that could make an app stop responding.1
    CVE-2026-47302: denial of service.
  • Addresses a flaw that could let an attacker get around a security check.2
    CVE-2026-47304: security feature bypass.
  • Addresses a flaw that could make an app stop responding.3
    CVE-2026-50304: denial of service.
  • Addresses a flaw that could make an app stop responding.4
    CVE-2026-50324: denial of service.
  • Addresses a flaw that could make an app stop responding.5
    CVE-2026-50355: denial of service.
  • Addresses a flaw that could make an app stop responding.6
    CVE-2026-50368: denial of service.
  • Addresses a flaw that could make an app stop responding.7
    CVE-2026-50411: denial of service.
  • Addresses a flaw that could make an app stop responding.8
    CVE-2026-50525: denial of service.
  • Addresses a flaw that could make an app stop responding.9
    CVE-2026-50527: denial of service.
  • Addresses a flaw that could let an attacker gain higher access.10
    CVE-2026-50646: elevation of privilege.
  • Addresses a flaw that could make an app stop responding.11
    CVE-2026-50647: denial of service.
  • Addresses a flaw that could make an app stop responding.12
    CVE-2026-50648: denial of service.
  • Addresses a flaw that could let an attacker run code.13
    CVE-2026-50649: remote code execution.
  • Addresses a flaw that could let an attacker gain higher access.14
    CVE-2026-50650: elevation of privilege.
  • Addresses a flaw that could make an app stop responding.15
    CVE-2026-50652: denial of service.
  • Addresses a flaw that could make an app stop responding.16
    CVE-2026-50653: denial of service.
  • Addresses a flaw that could let an attacker change data.17
    CVE-2026-50659: tampering.

.NET Libraries

For: Windows Server 2022 devices using .NET apps

  • Some secure web requests that could hang in certain setups are addressed.18
    Addresses an issue with synchronous HttpWebRequest connections in specific secure connection scenarios with certain server configurations.

.NET Runtime

For: Developers using the Visual Studio x86 native debugger

  • Some floating-point values are reported more accurately during debugger steps in mixed-code apps.19
    Addresses an issue in the Visual Studio x86 native debugger during step operations in mixed-code applications.

Technical details

Data sheet · Security · Downloads · Components Click to collapse or expand

Data sheet

Released
2026-07-14
Classification
Security Updates
Type
Cumulative update
Restart
Required
Replaces
KB5087059, KB5082425
Replaced by
KB5120714
VersionFile versionChannel
3.5 2.0.50727.9182 General availability
4.8.1 4.8.9339.0 General availability

Security

17 vulnerabilities fixed
17 important
VulnerabilitySeverityCVSS
CVE-2026-47304
.NET Security Feature Bypass Vulnerability
 Important 8.1
CVE-2026-50646
.NET Framework Remote Code Execution Vulnerability
 Important 7.8
CVE-2026-50649
.NET Remote Code Execution Vulnerability
 Important 7.8
CVE-2026-50650
.NET Framework Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-47302
.NET Denial of Service Vulnerability
 Important 7.5
CVE-2026-50304
Windows Active Directory Federation Services Denial of Service Vulnerability
 Important 7.5
CVE-2026-50355
Windows Active Directory Federation Services Denial of Service Vulnerability
 Important 7.5
CVE-2026-50368
Windows Active Directory Federation Services Denial of Service Vulnerability
 Important 7.5
CVE-2026-50411
Windows Active Directory Federation Services Denial of Service Vulnerability
 Important 7.5
CVE-2026-50525
.NET Denial of Service Vulnerability
 Important 7.5
CVE-2026-50527
.NET Framework Denial of Service Vulnerability
 Important 7.5
CVE-2026-50647
Active Directory Federation Server Denial of Service Vulnerability
 Important 7.5
CVE-2026-50648
.NET Framework Denial of Service Vulnerability
 Important 7.5
CVE-2026-50652
Azure Active Directory Denial of Service Vulnerability
 Important 7.5
CVE-2026-50653
Azure Active Directory Denial of Service Vulnerability
 Important 7.5
CVE-2026-50659
.NET Spoofing Vulnerability
 Important 6.5
CVE-2026-50324
Windows Active Directory Federation Services Denial of Service Vulnerability
 Important 5.9

Downloads (Microsoft Update Catalog)

x64 Windows Server 2022
76.2 MB
windows10.0-kb5101005-x64-ndp481.msu Main update · KB5101005 SHA-1: 0de76629…011054

Updated components

111 files changed since the previous update for the same versions.

Top changed componentsFiles
WPF28
WCF14
.NET runtime (CLR)12
.NET networking6
.NET data access2

Sources

Updated
Cited passages from Microsoft's official notes (19)
  1. 1. This security update addresses a denial of service vulnerability detailed in CVE-2026-47302. support.microsoft.com
  2. 2. This security update addresses a security feature bypass vulnerability detailed in CVE-2026-47304. support.microsoft.com
  3. 3. This security update addresses a denial of service vulnerability detailed in CVE-2026-50304. support.microsoft.com
  4. 4. This security update addresses a denial of service vulnerability detailed in CVE-2026-50324. support.microsoft.com
  5. 5. This security update addresses a denial of service vulnerability detailed in CVE-2026-50355. support.microsoft.com
  6. 6. This security update addresses a denial of service vulnerability detailed in CVE-2026-50368. support.microsoft.com
  7. 7. This security update addresses a denial of service vulnerability detailed in CVE-2026-50411. support.microsoft.com
  8. 8. This security update addresses a denial of service vulnerability detailed in CVE-2026-50525. support.microsoft.com
  9. 9. This security update addresses a denial of service vulnerability detailed in CVE-2026-50527. support.microsoft.com
  10. 10. This security update addresses an elevation of privilege vulnerability detailed in CVE-2026-50646. support.microsoft.com
  11. 11. This security update addresses a denial of service vulnerability detailed in CVE-2026-50647. support.microsoft.com
  12. 12. This security update addresses a denial of service vulnerability detailed in CVE-2026-50648. support.microsoft.com
  13. 13. This security update addresses a remote code execution vulnerability detailed in CVE-2026-50649. support.microsoft.com
  14. 14. This security update addresses an elevation of privilege vulnerability detailed in CVE-2026-50650. support.microsoft.com
  15. 15. This security update addresses a denial of service vulnerability detailed in CVE-2026-50652. support.microsoft.com
  16. 16. This security update addresses a denial of service vulnerability detailed in CVE-2026-50653. support.microsoft.com
  17. 17. This security update addresses a tampering vulnerability detailed in CVE-2026-50659. support.microsoft.com
  18. 18. Addresses an issue with synchronous HttpWebRequest connections where requests could hang in specific secure connection scenarios with certain server configurations. support.microsoft.com
  19. 19. Addresses an issue in the Visual Studio x86 native debugger where certain floating-point values could be reported incorrectly during step operations in mixed-code applications. support.microsoft.com
Checked automatically: 8 of 8 checks passed, 19 quoted passages · compared with Microsoft's page on Sep 25, 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 4/5, clarity 5/5, completeness 5/5. 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