CVE-2026-21253: CWE-416: Use After Free in Microsoft Windows 10 Version 1607
Use after free in Mailslot File System allows an authorized attacker to elevate privileges locally.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-21253) involves a use-after-free condition in the Mailslot File System of Windows 10 Version 1607 (build 10.0.14393.0). Exploitation requires local access with limited privileges and no user interaction. Successful exploitation could lead to elevation of privileges, impacting confidentiality, integrity, and availability of the system. Microsoft has published an official fix for this vulnerability.
Potential Impact
An authorized attacker with local access and limited privileges could exploit this use-after-free vulnerability to elevate their privileges. This could result in full control over the affected system, compromising 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 by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21253 to remediate this vulnerability.
CVE-2026-21253: CWE-416: Use After Free in Microsoft Windows 10 Version 1607
Description
Use after free in Mailslot File System allows an authorized attacker to elevate privileges locally.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-21253) involves a use-after-free condition in the Mailslot File System of Windows 10 Version 1607 (build 10.0.14393.0). Exploitation requires local access with limited privileges and no user interaction. Successful exploitation could lead to elevation of privileges, impacting confidentiality, integrity, and availability of the system. Microsoft has published an official fix for this vulnerability.
Potential Impact
An authorized attacker with local access and limited privileges could exploit this use-after-free vulnerability to elevate their privileges. This could result in full control over the affected system, compromising 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 by Microsoft as detailed in the vendor advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21253 to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2025-12-11T21:02:05.736Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21253","vendor":"Microsoft"}]
Threat ID: 698b76004b57a58fa120a035
Added to database: 2/10/2026, 6:16:32 PM
Last enriched: 5/12/2026, 5:13:05 AM
Last updated: 5/22/2026, 11:51:57 AM
Views: 143
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