Microsoft adds a Remote Desktop issue to its October Windows 11 update

Microsoft added a Remote Desktop connection failure to its known-issues notes for the October Windows 11 update on October 14, a day after releasing the update. The main package, KB5127648, covers Windows 11 versions 24H2, 25H2 and 26H2; separate packages serve 26H1 and 23H2. Microsoft also lists an issue affecting some USB Audio Class 1.0 devices.

Which October KB applies to each Windows 11 version?

The package and build depend on your Windows 11 version. Microsoft released the updates on October 13, 2026, with these version-to-build mappings:

Microsoft lists KB5127648 for all editions of 24H2, 25H2 and 26H2. It also lists the separate KB5127646 and KB5126653 updates for all editions of 26H1 and 23H2, respectively. Microsoft’s KB5127648 release notes, KB5127646 notes and KB5126653 notes also describe security improvements and fixes. For KB5127648, Microsoft lists changes involving Windows Explorer in multi-user environments, AC-3 audio playback, Always On VPN, Storage Spaces Direct, printing, gaming mouse stutter and Windows Hello fingerprint sign-in.

Security fixes and the reported threat tally

Action1 reports that October’s Patch Tuesday included 1,409 patches, 80 critical vulnerabilities and two zero-days. The figures count different things: Action1’s total is patches, while the critical and zero-day figures count vulnerabilities. Action1’s advisory also reports that CVE-2026-96951 was being exploited in the wild.

The National Vulnerability Database (NVD) describes CVE-2026-96951 as a Windows Shell command-injection flaw that allows an unauthorized attacker to bypass a security feature over a network. NVD records the vulnerability in the Cybersecurity and Infrastructure Security Agency’s Known Exploited Vulnerabilities Catalog. It lists a CVSS 3.1 score of 8.8 from Microsoft, the vulnerability’s assigning authority.

Known issues in KB5127648

Microsoft’s Remote Desktop notice concerns some non-admin users connecting to remote devices with Administrator protection enabled. Affected users may receive error 0xC000000D. Microsoft says IT administrators can temporarily turn off Administrator protection through their existing policy management method, and that it is working on a future fix.

The other listed issue affects some USB Audio Class 1.0 devices, which may fail to start or produce audio, show Code 10, or have unresponsive controls. Microsoft says the issue is limited to that device class. An earlier out-of-band update, KB5129195, partially resolved symptoms involving 8-channel or 3D-audio modes; other symptoms remain under investigation. Microsoft’s KB5127648 notes describe both issues and the stated mitigation.

Support notices apply to specific editions

Microsoft says the October 2026 monthly security update is the last update for Windows 11 24H2 Home and Pro. That notice applies to those editions; Microsoft lists KB5127648 for all 24H2 editions.

For Windows 11 23H2 Enterprise and Education, Microsoft schedules the end of updates for November 10, 2026. The date is a scheduled deadline, not a completed milestone. Microsoft’s 23H2 release notes give the edition-specific date.

How to get KB5127648

Microsoft says KB5127648 downloads and installs automatically through Windows Update. It is also available through the Microsoft Update Catalog and, for organizations, Windows Update for Business and Windows Server Update Services (WSUS). If you install a standalone Arm64 or x64 package, Microsoft says a required checkpoint cumulative update may need to be installed first.