IMPORTANT: This notice only affects environments where Scan Cab is used to check for update compliance.
What and why:
The September 2026 Scan Cab was made available at 2:00 PM PDT today, September 8, 2026. It helps determine whether a Windows device needs security updates without connecting to the Windows Update service.
Note: This Scan Cab does not include metadata for Microsoft Office update (
KB5002923). An additional Scan Cab covering it will follow. Deploy the September 2026 Scan Cab now, and deploy the new Scan Cab when it becomes available.
Rollout schedule:
The September 2026 Scan Cab is available now. An additional Scan Cab with metadata for KB5002923 will follow, with timing communicated as more information becomes available.
Who is affected:
The Wsusscn2.cab file is a cabinet file that is signed by Microsoft and contains information about Microsoft security-related updates. Devices that aren't connected to the Internet can be scanned to see whether these security-related updates are present or required. The Wsusscn2.cab file doesn't contain the security updates themselves so you must obtain and install any needed security-related updates through other means.
What will happen:
You can download and deploy the September 2026 Scan Cab via the usual processes. For detailed guidance, see the Additional information section below.
No action is required on environments where Scan Cab is not employed. However, please note that there might be non-Microsoft applications which utilize Scan Cab. Review the documentation for any software and update deployment tools used in your organization to understand if this is applicable in your environment.
Additional information: