The Update BureauKB5087538: Cumulative update for Windows Server, version 2019, May 2026. Remote Desktop warnings and account sign-in failures fixed
In short
The update fixes a Remote Desktop security warning display problem and a Microsoft account sign-in failure. It also expands the phased delivery of new Secure Boot certificates.
Does it affect you? Applies to: Devices running Windows Server 2019, x64.
Review notes Additional details from the official release notes (1) Read note
- In detail Secure Boot certificates used by most Windows devices have started expiring in June 2026. If not updated in time, this may affect certain personal and business devices’ ability to boot securely.
The official sources are linked at the end of the page.
Microsoft publishes separate notes for this KB for Windows 10.
What changes
Improvements 4 changes
Secure Boot
Gradual rollout
Verified in package
2 items
-
Windows Security can report the device's Secure Boot state.1
Enables dynamic status reporting for Secure Boot states in Windows Security App.
-
More eligible devices can automatically receive new Secure Boot certificates, in a controlled, phased rollout after showing enough successful update signals.2
Windows quality updates include additional high confidence device targeting data to increase coverage of devices eligible to automatically receive new Secure Boot certificates.
Daylight Savings Time
- Daylight saving time support is updated for the Arab Republic of Egypt to follow the government's 2023 change order.3
Servicing stack update
-
Devices hosted on Azure get enhanced verification of their Azure hosting status using an updated certificate chain.4
The included servicing stack update, KB5089760, adds enhanced logic to verify whether a device is hosted on Azure.
Fixes 2 changes
Remote Desktop security warnings
Verified in package
-
The Remote Desktop Connection security warning dialog displays correctly in multi-monitor setups with different display scaling settings.5
The issue might occur after installing a Windows security update released on or after April 14, 2026.
Sign-In
-
Some users can sign in to apps with a Microsoft account without a false “no Internet” error blocking access to Microsoft services and apps such as Microsoft Teams.6
The issue might occur after installing a Windows update released on or after March 10, 2026, even when the device has a working Internet connection.
New feature 1 change
Secure Boot
Verified in package
-
Eligible devices get a
C:\Windows\SecureBootfolder containing example scripts for checking certificate update status and automating deployment.7The scripts are intended for organizations with IT professionals managing device fleets and support a safe rollout mechanism in an Active Directory environment.
Technical details
Data sheet · Security · Downloads · Components Click to collapse or expand
Data sheet
- Released
- 2026-05-12
- Classification
- Security Updates
- Type
- Cumulative update
- Restart
- Required
- Replaces
- KB5091573, KB5082123, KB5078752, KB5075904
- Replaced by
- KB5094123
| Version | Build | Channel |
|---|---|---|
| 2019 | 17763.8755 | General availability |
Security
| Vulnerability | Severity | CVSS |
|---|---|---|
|
Windows Netlogon Remote Code Execution Vulnerability
|
Critical | 9.8 |
|
Windows Graphics Component Remote Code Execution Vulnerability
|
Critical | 8.8 |
|
Windows GDI Remote Code Execution Vulnerability
|
Critical | 7.8 |
|
Windows Native WiFi Miniport Driver Remote Code Execution Vulnerability
|
Critical | 7.5 |
The table lists the 4 exploited, publicly disclosed or critical vulnerabilities. See all 55 vulnerabilities →
Downloads (Microsoft Update Catalog)
x64
2019
818.6 MB
Updated components
1,185 files changed since the previous update for the same versions.
| Top changed components | Files |
|---|---|
| Graphics and display | 11 |
| Networking | 8 |
| Secure Boot | 8 |
| Hyper-V and virtualization | 7 |
| Security and sign-in | 6 |
| Storage and file systems | 5 |
| Audio | 4 |
| File Explorer and shell | 3 |
| Kernel | 3 |
| Remote Desktop | 2 |
| Printing | 1 |
| Settings | 1 |
Verified in package: changed files confirm Secure Boot, Remote Desktop security warnings.
Sources
Updated
Cited passages from Microsoft's official notes (7)
-
1.
This update enables dynamic status reporting for Secure Boot states in Windows Security App.
support.microsoft.com -
2.
With this update, Windows quality updates include additional high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates.
support.microsoft.com -
3.
Update for Arab Republic of Egypt to support the government DST change order in 2023.
support.microsoft.com -
4.
This servicing stack update (SSU) includes enhanced logic to verify whether a device is hosted on Azure, leveraging an updated certificate chain for validation.
support.microsoft.com -
5.
Fixed: The Remote Desktop Connection security warning dialog might render incorrectly in multi-monitor configurations with different display scaling settings.
support.microsoft.com -
6.
Fixed: After you install the Windows update released on or after March 10, 2026, some users might experience an issue signing in to apps with a Microsoft account.
support.microsoft.com -
7.
This update adds a new
support.microsoft.comSecureBootfolder underC:\Windowson eligible devices.
Checked automatically: 8 of 8 checks passed, 7 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 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