CVE-2021-25195HighCVSS 7.8

Windows PKU2U Elevation of Privilege Vulnerability

Published
February 9, 2021
Last Modified
—

🔗 CVE IDs covered (1)

CVE-2021-25195 →

📋 Description

What is PKU2U? PKU2U is a peer-to-peer authentication protocol. This setting prevents online identities from authenticating to domain-joined systems. Authentication will be centrally managed with Windows user accounts. How do I know if my servers are exploitable by this vulnerability? If your servers are not configured to allow the use of PKU2U authentication, they would not be vulnerable. In all cases, Microsoft strongly recommends that you install the updates for this vulnerability as soon as possible even if you do not use PKU2U authentication. Please see Network security Allow PKU2U authentication requests to this computer to use online identities for more information.

🎯 Affected products36

  • Windows 10 Version 1607 for 32-bit Systems
  • Windows 10 Version 1607 for x64-based Systems
  • Windows 10 Version 1803 for 32-bit Systems
  • Windows 10 Version 1803 for ARM64-based Systems
  • Windows 10 Version 1803 for x64-based Systems
  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for ARM64-based Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows 10 Version 1909 for 32-bit Systems
  • Windows 10 Version 1909 for ARM64-based Systems
  • Windows 10 Version 1909 for x64-based Systems
  • Windows 10 Version 2004 for 32-bit Systems
  • Windows 10 Version 2004 for ARM64-based Systems
  • Windows 10 Version 2004 for x64-based Systems
  • Windows 10 Version 20H2 for 32-bit Systems
  • Windows 10 Version 20H2 for ARM64-based Systems
  • Windows 10 for 32-bit Systems
  • Windows 10 for x64-based Systems
  • Windows 7 for 32-bit Systems Service Pack 1
  • Windows 7 for x64-based Systems Service Pack 1
  • Windows 8.1 for 32-bit systems
  • Windows 8.1 for x64-based systems
  • Windows RT 8.1
  • 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 2012
  • Windows Server 2012 (Server Core installation)
  • Windows Server 2012 R2
  • Windows Server 2012 R2 (Server Core installation)
  • Windows Server 2016
  • +6 more not shown

✅ Remediation

KB4601319 (Security Update) KB4601354 (Security Update) KB4601345 (Security Update) KB4601315 (Security Update) KB4601331 (Security Update) KB4601318 (Security Update) KB4601347 (Monthly Rollup) KB4601363 (Security Only) KB4601384 (Monthly Rollup) KB4601349 (Security Only) KB4601348 (Monthly Rollup) KB4601357 (Security Only)

🔗 References (23)