CVE-2026-85921: CWE-415: Double Free in Microsoft Windows 11 version 26H1
CVE-2026-85921 is a high-severity vulnerability in Microsoft Windows 11 version 26H1 involving a double free flaw in the Windows Secure Kernel Mode. This flaw allows an authorized local attacker with high privileges to elevate their privileges further. The vulnerability has been officially fixed by Microsoft.
AI Analysis
Technical Summary
CVE-2026-85921 is a double free vulnerability (CWE-415) in the Windows Secure Kernel Mode component of Microsoft Windows 11 version 26H1. The flaw allows an attacker who already has authorized local access with high privileges to exploit the double free condition to elevate their privileges. The vulnerability has a CVSS 3.1 base score of 8.2, indicating high severity, with impact on confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability.
Potential Impact
An authorized local attacker with high privileges can exploit this double free vulnerability to elevate their privileges further, potentially gaining full control over the affected system. The vulnerability impacts confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. It is recommended to apply the security update provided by Microsoft to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-85921: CWE-415: Double Free in Microsoft Windows 11 version 26H1
Description
CVE-2026-85921 is a high-severity vulnerability in Microsoft Windows 11 version 26H1 involving a double free flaw in the Windows Secure Kernel Mode. This flaw allows an authorized local attacker with high privileges to elevate their privileges further. The vulnerability has been officially fixed by Microsoft.
CVSS v3.1
Score 8.2high
Affected software
Microsoft
Windows 11 version 26H1
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-85921 is a double free vulnerability (CWE-415) in the Windows Secure Kernel Mode component of Microsoft Windows 11 version 26H1. The flaw allows an attacker who already has authorized local access with high privileges to exploit the double free condition to elevate their privileges. The vulnerability has a CVSS 3.1 base score of 8.2, indicating high severity, with impact on confidentiality, integrity, and availability. Microsoft has released an official fix for this vulnerability.
Potential Impact
An authorized local attacker with high privileges can exploit this double free vulnerability to elevate their privileges further, potentially gaining full control over the affected system. The vulnerability impacts confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. It is recommended to apply the security update provided by Microsoft to remediate this issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-04T18:24:41.250Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-85921","vendor":"Microsoft"}]
Threat ID: 6aa8300055bf5e2cf5600a62
Added to database: 09/14/2026, 17:33:52 UTC
Last enriched: 09/14/2026, 17:46:51 UTC
Last updated: 09/14/2026, 17:49:02 UTC
Views: 3
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