CVE-2020-17049HighCVSS 6.6

Kerberos KDC Security Feature Bypass Vulnerability

Published
November 10, 2020
Last Modified
—

🔗 CVE IDs covered (1)

CVE-2020-17049 →

📋 Description

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 products18

  • Windows Server 2008 R2 for x64-based Systems Service Pack 1
  • Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)
  • Windows Server 2008 for 32-bit Systems Service Pack 2
  • Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)
  • Windows Server 2008 for x64-based Systems Service Pack 2
  • Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)
  • Windows Server 2012
  • Windows Server 2012 (Server Core installation)
  • Windows Server 2012 R2
  • Windows Server 2012 R2 (Server Core installation)
  • Windows Server 2016
  • Windows Server 2016 (Server Core installation)
  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server, version 1903 (Server Core installation)
  • Windows Server, version 1909 (Server Core installation)
  • Windows Server, version 2004 (Server Core installation)
  • Windows Server, version 20H2 (Server Core Installation)

✅ Remediation

KB5004244 (Security Update) — fixed build 10.0.17763.2061 KB5001337 (Security Update) KB4592449 (Security Update) KB5004237 (Security Update) — fixed build 10.0.19041.1110 KB5004238 (Security Update) — fixed build 10.0.14393.4530 KB5004305 (Monthly Rollup) — fixed build 6.0.6003.21167 KB5004299 (Security Only) — fixed build 6.0.6003.21167 KB5004289 (Monthly Rollup) — fixed build 6.1.7601.25661 KB5004307 (Security Only) — fixed build 6.1.7601.25661 KB5004294 (Monthly Rollup) — fixed build 6.2.9200.23409 KB5004302 (Security Only) — fixed build 6.2.9200.23409 KB5004298 (Monthly Rollup) — fixed build 6.3.9600.20069 KB5004285 (Security Only) — fixed build 6.3.9600.20069

🔗 References (27)