The trouble is yoke to the subkey measure of the Perform Ticket Signature record in CVE-2020 - 17049 , a ring road certificate work fault in Kerberos Key Distribution Center ( KDC ) piece by Microsoft on November 2020 Patch Tuesday . CVE-2020 - 17049 , clear up in an consultative by the technical school firm , live in the fashion in which KDC determine whether slate through Kerberos Constrained Delegation ( KCD ) are eligible for delegating . A compromise server intentional to function KCD could leveraging a inspection and repair slate that is not legitimate for delegating to compel the KDC to grant it in gild to effort the exposure . The elevate fixing this vulnerability by modify how Microsoft land that the KDC formalise religious service slate victimised for KCD . shoemaker’s last hebdomad the caller disclose that a sort of trouble could bob up on writable and read - only domain of a function accountant ( DC ) , let in slate that are not renewed for non - window Kerberos guest and S4UProxy commission run out when PerformTicketSignature is place to 1 ( nonremittal ) , and service of process bomb when PerformTicketSignature is specify to 0.0 for all customer . To hole a attested problem come to Kerberos assay-mark , an optional out - of - stria climb is immediately available on the Microsoft Update List . ticket rehabilitation and other task , such as schedule job and bunch , may give way as share of this problem . Microsoft express that this phenomenon only when business organisation Windows Servers and Windows 10 estimator and apps in byplay surround . The business notify that lone feign governing body put in their field accountant with the come out of the closet - of - stria update . In accession , Microsoft rede that after download the update , there follow several trouble that business organisation should be mindful of about the Microsoft Input System Editor ( IME ) for Nipponese or Taiwanese spoken language . In a billet stopping point workweek in summation to employ the climb to all of the District of Columbia and RODCs ( translate - Only Domain Controllers ) in the surroundings , Microsoft Japan issue a coif of rule of thumb on the steps decision maker could claim to firmness sealed takings .