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TI-2026-16943 Aliases CVE-2026-20920GHSA-8264-x5xf-gjhc

Win32k Elevation of Privilege Vulnerability

Priority LOW 37CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Privilege escalation
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Microsoft. Impact type from Microsoft.

Summary

Use after free in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00493 42nd percentileScored 2026-11-07
Fix Fixed Microsoft: 3 updates

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftWindows 11 version 23H210.0.22631.0 to before 10.0.22631.649110.0.22631.6491Patch availableCNA
MicrosoftWindows 11 Version 23H210.0.22631.0 to before 10.0.22631.649110.0.22631.6491Patch availableCNA
MicrosoftWindows Server 202210.0.20348.0 to before 10.0.20348.464810.0.20348.4648Patch availableCNA
MicrosoftWindows Server 2022, 23H2 Edition (Server Core installation)10.0.25398.0 to before 10.0.25398.209210.0.25398.2092Patch availableCNA
  • Windows 11 version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.6491 Fixed in 10.0.22631.6491 Patch available CNA
  • Windows 11 Version 23H2 VendorMicrosoft Affected 10.0.22631.0 to before 10.0.22631.6491 Fixed in 10.0.22631.6491 Patch available CNA
  • Windows Server 2022 VendorMicrosoft Affected 10.0.20348.0 to before 10.0.20348.4648 Fixed in 10.0.20348.4648 Patch available CNA
  • Windows Server 2022, 23H2 Edition (Server Core installation) VendorMicrosoft Affected 10.0.25398.0 to before 10.0.25398.2092 Fixed in 10.0.25398.2092 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:*before 10.0.22631.6491VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*before 10.0.20348.4648VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*before 10.0.25398.2092VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:* Versions before 10.0.22631.6491 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:* Versions before 10.0.20348.4648 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:* Versions before 10.0.25398.2092 Vulnerable ·Microsoft

Remediation

Microsoft 3 updates

  • KB5073457
    Security Update
    • Windows Server 2022 10.0.20348.4648
    • Windows Server 2022 (Server Core installation) 10.0.20348.4648
  • KB5073455
    Security Update
    • Windows 11 Version 23H2 for ARM64-based Systems 10.0.22631.6491
    • Windows 11 Version 23H2 for x64-based Systems 10.0.22631.6491
  • KB5073450
    Security Update
    • Windows Server 2022, 23H2 Edition (Server Core installation) 10.0.25398.2092

Vendor assessments

Microsoft

Microsoft's page for this CVE →

Impact
Elevation of Privilege
Exploited
No
Publicly disclosed
No
Exploitability
Exploitation Unlikely

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-20920
  2. 2026-10-03 Alias added: GHSA-8264-x5xf-gjhc

References

Patch 1

  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-73128 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-17367 MSHTML Framework Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-17364 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2025-24062 Windows SMB Client Elevation of Privilege Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2025-24042 Internet Shortcut Files Remote Code Execution Vulnerability KEVCVSS 3.1HIGH 8.8
See all 3407 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences