Microsoft releases Update KB4594440 Windows 10 build 19042.631
Improvements and fixes:
This non-security update includes quality improvements. Key changes include:
- This build includes all the improvements from Windows 10, version 2004.
- No additional issues were documented for this release.
- Addresses issues with Kerberos authentication related to the PerformTicketSignature registry subkey value in CVE-2020-17049, which was a part of the November 10, 2020 Windows update. The following issues might occur on writable and read-only domain controllers (DC):
- Kerberos service tickets and ticket-granting tickets (TGT) might not renew for non-Windows Kerberos clients when PerformTicketSignature is set to 1 (the default).
- Service for User (S4U) scenarios, such as scheduled tasks, clustering, and services for line-of-business applications, might fail for all clients when PerformTicketSignature is set to 0.
- S4UProxy delegation fails during ticket referral in cross-domain scenarios if DCs in intermediate domains are inconsistently updated and PerformTicketSignature is set to 1.
