CVE-2026-20871: CWE-416: Use After Free in Microsoft Windows 10 Version 21H2
Use after free in Desktop Windows Manager allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-20871) involves a use-after-free condition in the Desktop Windows Manager on Windows 10 Version 21H2 (build 10.0.19044.0). An authorized local attacker can exploit this flaw to elevate their privileges, potentially gaining higher-level access than intended. The CVSS 3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability. The vulnerability requires local access with low complexity and no user interaction. A patch is available from Microsoft to remediate this issue.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, potentially leading to full system compromise or unauthorized access to sensitive resources. The vulnerability impacts confidentiality, integrity, and availability of the affected system. No public exploits are currently known.
Mitigation Recommendations
A patch is available to remediate this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 21H2 (build 10.0.19044.0) as soon as possible to mitigate the risk. Since this is a local privilege escalation, restricting local access to trusted users also reduces risk.
CVE-2026-20871: CWE-416: Use After Free in Microsoft Windows 10 Version 21H2
Description
Use after free in Desktop Windows Manager allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-20871) involves a use-after-free condition in the Desktop Windows Manager on Windows 10 Version 21H2 (build 10.0.19044.0). An authorized local attacker can exploit this flaw to elevate their privileges, potentially gaining higher-level access than intended. The CVSS 3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability. The vulnerability requires local access with low complexity and no user interaction. A patch is available from Microsoft to remediate this issue.
Potential Impact
Successful exploitation allows an authorized local attacker to elevate privileges, potentially leading to full system compromise or unauthorized access to sensitive resources. The vulnerability impacts confidentiality, integrity, and availability of the affected system. No public exploits are currently known.
Mitigation Recommendations
A patch is available to remediate this vulnerability. It is recommended to apply the official Microsoft update for Windows 10 Version 21H2 (build 10.0.19044.0) as soon as possible to mitigate the risk. Since this is a local privilege escalation, restricting local access to trusted users also reduces risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-03T05:54:20.382Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 69668ae1a60475309f9ae166
Added to database: 1/13/2026, 6:11:45 PM
Last enriched: 4/3/2026, 12:47:52 PM
Last updated: 5/8/2026, 7:27:29 PM
Views: 87
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