CVE-2026-20920: CWE-416: Use After Free in Microsoft Windows 11 version 23H2
Use after free in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20920) involves a use-after-free condition in the Windows Win32K ICOMP component on Windows 11 version 23H2 (build 10.0.22631.0). Exploitation requires local access with some privileges and can lead to elevation of privileges, impacting confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, potentially gaining higher system privileges and full control over the affected system. The CVSS 3.1 base score is 7.8 (High), reflecting significant impact on confidentiality, integrity, and availability.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20920 to remediate this vulnerability.
CVE-2026-20920: CWE-416: Use After Free in Microsoft Windows 11 version 23H2
Description
Use after free in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.
CVSS v3.1
Score 7.8high
Affected software
Microsoft
Windows 11 version 23H2
Microsoft
Windows 11 Version 23H2
Microsoft
Windows Server 2022
Microsoft
Windows Server 2022, 23H2 Edition (Server Core installation)
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20920) involves a use-after-free condition in the Windows Win32K ICOMP component on Windows 11 version 23H2 (build 10.0.22631.0). Exploitation requires local access with some privileges and can lead to elevation of privileges, impacting confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, potentially gaining higher system privileges and full control over the affected system. The CVSS 3.1 base score is 7.8 (High), reflecting significant impact on confidentiality, integrity, and availability.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20920 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-04T20:04:16.335Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20920","vendor":"Microsoft"}]
Threat ID: 69668ae3a60475309f9ae1c0
Added to database: 01/13/2026, 18:11:47 UTC
Last enriched: 07/30/2026, 23:41:11 UTC
Last updated: 09/10/2026, 22:25:54 UTC
Views: 185
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