The Update BureauKB5078883: Cumulative update for Windows 11, version 23H2, March 2026. Secure Boot coverage expands; File History handles more filenames
In short
The update addresses 41 Important-severity vulnerabilities and broadens the rollout of new Secure Boot certificates. It also improves File History backups and stability for some graphics configurations.
Does it affect you? Applies to: Devices running Windows 11, version 23H2, on x64 or Arm64.
What changes
Improvements 7 changes
Secure Boot
Gradual rollout
Verified in package
-
More eligible devices can receive new Secure Boot certificates automatically, through a controlled, phased rollout.1
Windows quality updates include additional high confidence device targeting data. New certificates are delivered only after sufficient successful update signals.
File History
- File History in Control Panel now backs up files with names that include Chinese characters and Private Use Area characters.2
Graphics
2 items
-
Devices with certain GPU configurations shut down more reliably.3
Improves stability affecting certain GPU configurations.
-
Games and 3D apps run more reliably during intensive graphics use on certain GPU configurations.4
Improves stability for certain GPU configurations during intensive graphics use.
Texts and Fonts
- Windows fonts include the new Saudi Riyal currency symbol.5
Windows System Image Manager
-
A warning dialog helps you confirm that a catalog file you select comes from a trusted source.6
Improves the reliability of choosing trusted catalog files.
Servicing stack
-
The component that installs Windows updates gets quality improvements to help devices receive and install Microsoft updates reliably.7
Includes servicing stack update KB5079275, build 22621.6773.
New feature 1 change
Secure Boot
Verified in package
-
Two new PowerShell features help you check Secure Boot keys and certificates and whether your device follows the latest Secure Boot policy.8
Get-SecureBootUEFIsupports the-Decodedoption to display keys and certificates in a readable format.Get-SecureBootSVNreports the Secure Boot Security Version Number of the UEFI firmware and bootloader.
Technical details
Data sheet · Security · Downloads · Components Click to collapse or expand
Data sheet
- Released
- 2026-03-10
- Classification
- Security Updates
- Type
- Cumulative update
- Restart
- Required
- Replaces
-
KB5075941, KB5078132, KB5077797, KB5073455
+49 earlier
KB5071417, KB5070312, KB5068865, KB5067112, KB5066793, KB5065790, KB5065431, KB5064080, KB5066189, KB5063875, KB5062663, KB5062552, KB5060826, KB5060999, KB5062170, KB5058502, KB5058405, KB5055629, KB5058919, KB5055528, KB5053657, KB5053602, KB5052094, KB5051989, KB5050092, KB5050021, KB5048685, KB5046732, KB5046633, KB5044380, KB5044285, KB5043145, KB5043076, KB5041587, KB5041585, KB5040527, KB5040442, KB5039302, KB5039212, KB5037853, KB5037771, KB5036980, KB5036893, KB5035942, KB5035853, KB5034848, KB5034765, KB5034204, KB5034123 - Replaced by
- KB5082052
| Version | Build | Channel |
|---|---|---|
| 23H2 | 22631.6783 | General availability |
Security
| Vulnerability | Severity | CVSS |
|---|
The table lists the 0 exploited, publicly disclosed or critical vulnerabilities. See all 41 vulnerabilities →
Downloads (Microsoft Update Catalog)
x64
23H2
1.0 GB
Arm64
23H2
1.1 GB
Updated components
1,398 files changed since the previous update for the same versions.
| Top changed components | Files |
|---|---|
| Graphics and display | 27 |
| File Explorer and shell | 14 |
| Networking | 11 |
| Secure Boot | 11 |
| Storage and file systems | 9 |
| Kernel | 7 |
| Printing | 6 |
| Security and sign-in | 6 |
| Hyper-V and virtualization | 3 |
| Remote Desktop | 3 |
| Settings | 3 |
| Audio | 2 |
Verified in package: changed files confirm Secure Boot.
Sources
Updated
Cited passages from Microsoft's official notes (8)
-
1.
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 -
2.
Files with names that include Chinese characters and Private Use Area characters now back up successfully, helping keep your files protected and available when you need them.
support.microsoft.com -
3.
This update improves stability affecting certain GPU configurations, helping devices shut down more reliably.
support.microsoft.com -
4.
This update improves stability for certain GPU configurations. It helps games and 3D apps run more reliably during intensive graphics use.
support.microsoft.com -
5.
This update improves Windows fonts by adding the new Saudi Riyal currency symbol.
support.microsoft.com -
6.
It adds a warning dialog that helps you confirm that the file you select comes from a trusted source.
support.microsoft.com -
7.
This update makes quality improvements to the servicing stack, which is the component that installs Windows updates.
support.microsoft.com -
8.
This update introduces two new PowerShell features to help you manage the ongoing Secure Boot key rollout.
support.microsoft.com
Checked automatically: 7 of 8 checks passed, 8 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: not passed
A second AI read the text against the sources: correctness 4/5, clarity 4/5, 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