CVE-2020-17049

Summary

A security feature bypass vulnerability exists in the way Key Distribution Center (KDC) determines if a service ticket can be used for delegation via Kerberos Constrained Delegation (KCD). To exploit the vulnerability, a compromised service that is configured to use KCD could tamper with a service ticket that is not valid for delegation to force the KDC to accept it. The update addresses this vulnerability by changing how the KDC validates service tickets used with KCD.

Affected Software

VendorProductVersion RangeStatus
MicrosoftWindows Server 201910.0.0 < 10.0.17763.2061affected
MicrosoftWindows Server 2019 (Server Core installation)10.0.0 < 10.0.17763.2061affected
MicrosoftWindows Server, version 1909 (Server Core installation)10.0.0 < publicationaffected
MicrosoftWindows Server, version 1903 (Server Core installation)10.0.0 < publicationaffected
MicrosoftWindows Server version 200410.0.0 < 10.0.19041.1110affected
MicrosoftWindows Server 201610.0.0 < 10.0.14393.4530affected
MicrosoftWindows Server 2016 (Server Core installation)10.0.0 < 10.0.14393.4530affected
MicrosoftWindows Server 2008 Service Pack 26.0.0 < 6.0.6003.21167affected
MicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)6.0.0 < 6.0.6003.21167affected
MicrosoftWindows Server 2008 Service Pack 26.0.0 < 6.0.6003.21167affected
MicrosoftWindows Server 2008 R2 Service Pack 16.1.0 < 6.1.7601.25661affected
MicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)6.0.0 < 6.1.7601.25661affected
MicrosoftWindows Server 20126.2.0 < 6.2.9200.23409affected
MicrosoftWindows Server 2012 (Server Core installation)6.2.0 < 6.2.9200.23409affected
MicrosoftWindows Server 2012 R26.3.0 < 6.3.9600.20069affected
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.0 < 6.3.9600.20069affected
MicrosoftWindows Server version 20H210.0.0 < 10.0.19041.1110affected

Weaknesses

  • Security Feature Bypass

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References