CVE-2026-49173: CWE-416: Use After Free in Microsoft Windows 11 version 26H1
CVE-2026-49173 is a use-after-free vulnerability in the Windows Kernel of Microsoft Windows 11 version 26H1 (build 10.0.28000.0). This flaw allows an authorized local attacker to elevate privileges. The vulnerability has a high severity score of 7.8 and has an official fix available from Microsoft.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-49173) involves a use-after-free condition in the Windows Kernel on Windows 11 version 26H1 (build 10.0.28000.0). Exploitation requires local access with some privileges and does not require user interaction. Successful exploitation could lead to elevation of privileges, impacting confidentiality, integrity, and availability with high severity. Microsoft has published an official fix to address this issue.
Potential Impact
An authorized local attacker can exploit this use-after-free vulnerability to elevate their privileges on the affected Windows 11 system. This could allow the attacker to gain higher-level access than intended, potentially compromising system confidentiality, integrity, and availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49173 to remediate this vulnerability.
CVE-2026-49173: CWE-416: Use After Free in Microsoft Windows 11 version 26H1
Description
CVE-2026-49173 is a use-after-free vulnerability in the Windows Kernel of Microsoft Windows 11 version 26H1 (build 10.0.28000.0). This flaw allows an authorized local attacker to elevate privileges. The vulnerability has a high severity score of 7.8 and has an official fix available from Microsoft.
CVSS v3.1
Score 7.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-49173) involves a use-after-free condition in the Windows Kernel on Windows 11 version 26H1 (build 10.0.28000.0). Exploitation requires local access with some privileges and does not require user interaction. Successful exploitation could lead to elevation of privileges, impacting confidentiality, integrity, and availability with high severity. Microsoft has published an official fix to address this issue.
Potential Impact
An authorized local attacker can exploit this use-after-free vulnerability to elevate their privileges on the affected Windows 11 system. This could allow the attacker to gain higher-level access than intended, potentially compromising system confidentiality, integrity, and availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49173 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-05-27T23:44:09.623Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-49173","vendor":"Microsoft"}]
Threat ID: 6a566f6b68715ace43e6b3d5
Added to database: 07/14/2026, 17:18:35 UTC
Last enriched: 07/15/2026, 01:49:05 UTC
Last updated: 07/15/2026, 01:49:05 UTC
Views: 2
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