KB5065429: [WinSock] Fixed known issue

September 9, 2025—KB5065429 (OS Builds 19044.6332 and 19045.6332)

Summary
This security update includes fixes and quality improvements that are part of the following updates:

• August 12, 2025—KB5063709 (OS Builds 19044.6216 and 19045.6216)
• August 19, 2025—KB5066188 (OS Builds 19044.6218 and 19045.6218) Out-of-band
• August 26, 2025—KB5063842: Windows 10, version 22H2 (OS Build 19045.6278) Preview

The following is a summary of the issues that this update addresses when you install this update. If there are new features, it lists them as well. The bold text within the brackets indicates the item or area of the change we are documenting.

• [File Server] New! As part of the Windows updates released on and after September 9, 2025, this update enables support for IT administrators to deploy hardening measures for SMB. For detailed guidance, see CVE-2025-55234 | Windows SMB Elevation of Privilege Vulnerability.
• [WinSock] Fixed: This known issue occurred after installing the August 2025 Windows security update (KB5063709). You might experience delays or uneven audio and video performance issues when using Network Device Interface (NDI) to stream or transfer feeds between PCs.