CVE-2026-70580: Windows Credential Guard Spoofing Vulnerability

Overview

Severity
High (CVSS 8.8)
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C
Category
Spoofing
Exploit Status
Not Exploited
Exploitation Likelihood
Less Likely
Patch Tuesday
2026-Oct
Released
2026-10-13
EPSS Score
0.30% (percentile: 21.6%)

Description

Missing authentication for critical function in Windows Credential Guard allows an authorized attacker to perform spoofing locally.

FAQ

How could an attacker exploit this vulnerability? An authenticated attacker could exploit this vulnerability by causing the affected service to become unavailable and impersonating it when it restarts. Successful exploitation could allow the attacker to intercept or alter security operations. User interaction is not required.

Affected Products (24)

Windows

  • Windows 11 Version 26H2 for ARM64-based Systems
  • Windows 11 Version 26H2 for x64-based Systems
  • Windows 10 Version 1809 for 32-bit Systems
  • Windows 10 Version 1809 for x64-based Systems
  • Windows Server 2019
  • Windows Server 2019 (Server Core installation)
  • Windows Server 2022
  • Windows Server 2022 (Server Core installation)
  • Windows 10 Version 21H2 for 32-bit Systems
  • Windows 10 Version 21H2 for ARM64-based Systems
  • Windows 10 Version 21H2 for x64-based Systems
  • Windows Server 2025 (Server Core installation)
  • Windows 11 Version 25H2 for ARM64-based Systems
  • Windows 11 Version 25H2 for x64-based Systems
  • Windows 11 Version 23H2 for ARM64-based Systems
  • Windows 11 Version 23H2 for x64-based Systems
  • Windows 11 Version 24H2 for ARM64-based Systems
  • Windows 11 Version 24H2 for x64-based Systems
  • Windows Server 2025
  • Windows 11 version 26H1 for x64-based Systems
  • Windows 11 Version 26H1 for ARM64-based Systems

ESU

  • Windows 10 Version 22H2 for x64-based Systems
  • Windows 10 Version 22H2 for ARM64-based Systems
  • Windows 10 Version 22H2 for 32-bit Systems

Security Updates (7)

Acknowledgments

Microsoft Offensive Research & Security Engineering

Revision History

  • 2026-10-13: Information published.