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Windows 11 24H2 / 25H2 Windows 11 24H2 / 25H2 Security update
Patch Tuesday Zero-day

KB5077181

KB5077181: Cumulative update for Windows 11, versions 24H2 and 25H2, February 2026. Exploited Shell and MSHTML bypass flaws patched

In short

Fixes 27 vulnerabilities, including five that attackers are exploiting. It also addresses a WPA3 Wi-Fi connection problem and gaming eligibility checks.

Does it affect you? Applies to: Devices running Windows 11, version 25H2 or 24H2, on x64 or Arm64 processors.

Builds
26100.7840 · 26200.7840
Security
27 fixed · 5 exploited
Restart
Required

What changes

Improvements 5 changes

Catalog

  • The Catalog listing now has the corrected x64 package string.1
    The x64 .msu update string on the Catalog tab was corrected on June 4, 2026.

Update installation

  • The second MSU file in the individual-installation instructions has been updated.2
    The second MSU file listed in Method 2 was updated on February 24, 2026.

Secure Boot

Gradual rollout Verified in package
  • Windows uses device-targeting data to deliver new Secure Boot certificates in phases, after devices show enough successful update signals.3
    Quality updates include targeting data identifying devices and their ability to receive new Secure Boot certificates.

AI components

Verified in package
  • Four AI components are updated to version 1.2601.1268.0 on Copilot+ PCs.4
    Updates Image Search, Content Extraction, Semantic Analysis, and Settings Model to 1.2601.1268.0. These components apply only to Copilot+ PCs.

Servicing stack

  • The servicing stack, which installs Windows updates, receives quality improvements.5
    Includes servicing stack update KB5077869, build 26100.7839.

Fixes 2 changes

Gaming

  • Addresses an issue that affects device eligibility for the full-screen gaming experience.6

Networking

Verified in package
  • Addresses a problem that prevented some devices from connecting to certain WPA3-Personal Wi-Fi networks after installing KB5074105.7

Technical details

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

Data sheet

Released
2026-02-10
Classification
Security Updates
Type
Cumulative update
Restart
Required
Replaces
KB5074105, KB5078127, KB5077744, KB5074109
+42 earlier KB5072033, KB5070311, KB5068861, KB5067036, KB5070773, KB5066835, KB5065789, KB5068221, KB5065426, KB5064081, KB5063878, KB5062660, KB5064489, KB5062553, KB5060829, KB5063060, KB5060842, KB5058499, KB5061977, KB5058411, KB5055627, KB5059087, KB5055523, KB5053656, KB5053598, KB5052093, KB5051987, KB5050094, KB5050009, KB5048667, KB5046740, KB5046617, KB5044384, KB5044284, KB5043178, KB5043080, KB5041865, KB5041571, KB5040529, KB5040435, KB5039304, KB5039239
Replaced by
KB5079473
VersionBuildChannel
24H2 26100.7840 General availability
25H2 26200.7840 General availability

Security

27 vulnerabilities fixed
5 exploited 26 important 1 moderate
VulnerabilitySeverityCVSS
CVE-2026-21510 Exploited
Windows Shell Security Feature Bypass Vulnerability
 Important 8.8
CVE-2026-21513 Exploited
MSHTML Framework Security Feature Bypass Vulnerability
 Important 8.8
CVE-2026-21519 Exploited
Desktop Window Manager Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21533 Exploited
Windows Remote Desktop Services Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21525 Exploited
Windows Remote Access Connection Manager Denial of Service Vulnerability
 Moderate 6.2
CVE-2026-21255
Windows Hyper-V Security Feature Bypass Vulnerability
 Important 8.8
CVE-2026-21231
Windows Kernel Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21232
Windows HTTP.sys Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21236
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21238
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21239
Windows Kernel Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21240
Windows HTTP.sys Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21245
Windows Kernel Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21246
Windows Graphics Component Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-21250
Windows HTTP.sys Elevation of Privilege Vulnerability
 Important 7.8
CVE-2026-20846
GDI+ Denial of Service Vulnerability
 Important 7.5
CVE-2026-21244
Windows Hyper-V Remote Code Execution Vulnerability
 Important 7.3
CVE-2026-21247
Windows Hyper-V Remote Code Execution Vulnerability
 Important 7.3
CVE-2026-21248
Windows Hyper-V Remote Code Execution Vulnerability
 Important 7.3
CVE-2026-21234
Windows Connected Devices Platform Service Elevation of Privilege Vulnerability
 Important 7.0
CVE-2026-21237
Windows Subsystem for Linux Elevation of Privilege Vulnerability
 Important 7.0
CVE-2026-21241
Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
 Important 7.0
CVE-2026-21242
Windows Subsystem for Linux Elevation of Privilege Vulnerability
 Important 7.0
CVE-2026-21253
Mailslot File System Elevation of Privilege Vulnerability
 Important 7.0
CVE-2026-21508
Windows Storage Elevation of Privilege Vulnerability
 Important 7.0
CVE-2026-21222
Windows Kernel Information Disclosure Vulnerability
 Important 5.5
CVE-2026-21249
Windows NTLM Spoofing Vulnerability
 Important 3.3

Updated components

2,502 files changed since the previous update for the same versions.

Top changed componentsFiles
Settings103
Graphics and display30
File Explorer and shell23
Remote Desktop19
Hyper-V and virtualization16
Security and sign-in13
Printing9
Search8
Emoji and input6
Networking6
Audio5
Kernel5

Verified in package: changed files confirm Secure Boot, AI components, Networking.

Sources

Updated
Cited passages from Microsoft's official notes (7)
  1. 1. Corrected the x64 .msu update string on the Catalog tab for KB5077181 (this update) support.microsoft.com
  2. 2. the second MSU file listed in Method 2: Install each MSU file individually has been updated. support.microsoft.com
  3. 3. With this update, Windows quality updates include a broad set of targeting data that identifies devices and their ability to receive new Secure Boot certificates. support.microsoft.com
  4. 4. | Image Search | 1.2601.1268.0 | | Content Extraction | 1.2601.1268.0 | | Semantic Analysis | 1.2601.1268.0 | | Settings Model | 1.2601.1268.0 | support.microsoft.com
  5. 5. This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. support.microsoft.com
  6. 6. [Gaming] Fixed: This update addresses an issue that determines device eligibility for the full-screen gaming experience. support.microsoft.com
  7. 7. [Networking] Fixed: This update addresses an issue that prevented some devices from connecting to certain WPA3‑Personal Wi‑Fi networks. The issue might occur after you install KB5074105. support.microsoft.com
Checked automatically: 7 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: not passed

A second AI read the text against the sources: correctness 5/5, 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