What’s New in Windows 11 September 2025 Patch: KB5065426 & KB5065431

This month’s cumulative updates for Windows 11 deliver important security fixes, zero-day patches, and handy feature updates. Whether you’re on version 24H2, 23H2, or 22H2, here’s what you need to know—and why you should install the September 9, 2025 updates right away.

Two Critical Zero-Day Vulnerabilities Sealed

Microsoft addressed two publicly disclosed zero-day flaws:

• CVE-2025-55234: An SMB elevation of privilege bug marked “Exploitation More Likely.”

• CVE-2024-21907: An issue in Newtonsoft.Json handling that could allow privilege escalation; tagged “Exploitation Less Likely.”

Neither vulnerability showed active exploits in the wild—but both are now fully patched to protect your network and apps.

81 Total Security Fixes

Alongside the zero days, this release bundles fixes for 41 elevation-of-privilege issues, 22 remote-code-execution bugs, 16 information-disclosure vulnerabilities, and more. Key highlights:

• Kerberos stability improved when accessing cloud file shares

• Chinese IME typing glitch after a copy-paste operation is resolved

• Crashes in Sticky Notes, Notepad, and other apps due to textinputframework.dll are fixed

Handy New Features & Improvements

Beyond security, these updates enhance everyday workflows:

• Redesigned Permission Prompts: When apps request camera, mic, or location, the screen dims and the dialog appears front and center for clearer consent.

• Taskbar Clock Upgrade: Toggle seconds above the date in your notification center via Settings → Time & language → Date & time.

• Recall & Click to Do: New “Recall” home page shows recent snapshots of your top apps and sites. “Click to Do” offers quick tutorials on features like image-background removal.

• Lock Screen Widgets: Add, remove, and reorder widgets (Weather, Sports, Traffic, etc.) on your lock screen from Settings → Personalization → Lock screen.

• File Explorer Dividers & People Info: Context menus now have separators, and work-account sign-ins show live persona cards in the Details pane.

• Windows Hello & Passkeys: Redesigned sign-in UI, more reliable fingerprint unlock after standby, and broader Copilot+ support.

• Multiple Widget Dashboards: Create and switch between custom widget boards for personalized news and updates.

Patch Details by Version

Find these in the Microsoft Update Catalog by searching the KB number.

Known Issue Resolved

A UAC-prompt glitch that unexpectedly asked non-admin users for credentials during MSI repairs is now fixed. Systems updated to KB5065426 no longer trigger these unnecessary prompts.

Takeaway: Install KB5065426 or KB5065431 today to close two zero days, secure against dozens of flaws, and enjoy fresh UI and productivity enhancements.