CVE-2026-20877: CWE-416: Use After Free in Microsoft Windows 10 Version 1809
Use after free in Windows Management Services allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
CVE-2026-20877 is a use-after-free vulnerability (CWE-416) affecting Windows Management Services in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability enables an authorized local attacker to elevate privileges by exploiting improper memory handling. The issue has been assigned a CVSS v3.1 base score of 7.8, indicating high severity, with attack vector local, attack complexity high, privileges required low, no user interaction, and scope changed. Microsoft has released an official fix for this vulnerability as detailed in their security update guide.
Potential Impact
An authorized local attacker could exploit this use-after-free vulnerability to elevate their privileges on the affected system. This could lead to complete system compromise, including full control over confidentiality, integrity, and availability of the system.
Mitigation Recommendations
An official fix is available from Microsoft. It is recommended to apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20877 to remediate this vulnerability.
CVE-2026-20877: CWE-416: Use After Free in Microsoft Windows 10 Version 1809
Description
Use after free in Windows Management Services allows an authorized attacker to elevate privileges locally.
CVSS v3.1
Score 7.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-20877 is a use-after-free vulnerability (CWE-416) affecting Windows Management Services in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability enables an authorized local attacker to elevate privileges by exploiting improper memory handling. The issue has been assigned a CVSS v3.1 base score of 7.8, indicating high severity, with attack vector local, attack complexity high, privileges required low, no user interaction, and scope changed. Microsoft has released an official fix for this vulnerability as detailed in their security update guide.
Potential Impact
An authorized local attacker could exploit this use-after-free vulnerability to elevate their privileges on the affected system. This could lead to complete system compromise, including full control over confidentiality, integrity, and availability of the system.
Mitigation Recommendations
An official fix is available from Microsoft. It is recommended to apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20877 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-03T05:54:20.390Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20877","vendor":"Microsoft"}]
Threat ID: 69668ae1a60475309f9ae178
Added to database: 01/13/2026, 18:11:45 UTC
Last enriched: 07/30/2026, 23:41:39 UTC
Last updated: 09/10/2026, 19:36:52 UTC
Views: 262
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