CVE-2026-20842: CWE-416: Use After Free in Microsoft Windows 10 Version 21H2
Use after free in Windows DWM allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20842) involves a use-after-free condition in the Windows DWM component on Windows 10 Version 21H2 (build 10.0.19044.0). An authorized local attacker could exploit this flaw to elevate their privileges, potentially gaining higher-level access than intended. The vulnerability is classified under CWE-416 (Use After Free). The CVSS v3.1 base score is 7.0, reflecting high impact on confidentiality, integrity, and availability, with attack vector local, high attack complexity, and low privileges required. Microsoft has published this vulnerability and a patch is available to remediate it.
Potential Impact
Successful exploitation of this vulnerability allows an authorized local attacker to elevate privileges on the affected Windows 10 system. This could lead to unauthorized access to sensitive information, modification of system settings, or disruption of system availability. The CVSS score indicates high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 21H2 (build 10.0.19044.0) to remediate the issue. Since this is a local privilege escalation vulnerability, applying the patch will prevent attackers from exploiting this flaw to gain elevated privileges.
CVE-2026-20842: CWE-416: Use After Free in Microsoft Windows 10 Version 21H2
Description
Use after free in Windows DWM allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20842) involves a use-after-free condition in the Windows DWM component on Windows 10 Version 21H2 (build 10.0.19044.0). An authorized local attacker could exploit this flaw to elevate their privileges, potentially gaining higher-level access than intended. The vulnerability is classified under CWE-416 (Use After Free). The CVSS v3.1 base score is 7.0, reflecting high impact on confidentiality, integrity, and availability, with attack vector local, high attack complexity, and low privileges required. Microsoft has published this vulnerability and a patch is available to remediate it.
Potential Impact
Successful exploitation of this vulnerability allows an authorized local attacker to elevate privileges on the affected Windows 10 system. This could lead to unauthorized access to sensitive information, modification of system settings, or disruption of system availability. The CVSS score indicates high impact on confidentiality, integrity, and availability.
Mitigation Recommendations
A patch is available for this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 21H2 (build 10.0.19044.0) to remediate the issue. Since this is a local privilege escalation vulnerability, applying the patch will prevent attackers from exploiting this flaw to gain elevated privileges.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-03T05:54:20.376Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668adea60475309f9ae09d
Added to database: 1/13/2026, 6:11:42 PM
Last enriched: 4/3/2026, 12:44:50 PM
Last updated: 5/10/2026, 1:49:21 PM
Views: 74
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