CVE-2026-83997: CWE-416: Use After Free in Microsoft Windows 10 Version 21H2
Description
Use after free in Windows Message Queuing allows an unauthorized attacker to execute code over a network.
CVSS v3.1
Score 8.1high
Affected software
Microsoft
Windows 10 Version 21H2
Microsoft
Windows 10 Version 22H2
Microsoft
Windows 11 version 23H2
Microsoft
Windows 11 Version 23H2
Microsoft
Windows 11 Version 24H2
Microsoft
Windows 11 Version 25H2
Microsoft
Windows 11 version 26H1
Microsoft
Windows Server 2022
Microsoft
Windows Server 2025
Microsoft
Windows Server 2025 (Server Core installation)
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-83997 is a use-after-free vulnerability (CWE-416) in the Windows Message Queuing component of Microsoft Windows 10 Version 21H2. This flaw allows an attacker to execute arbitrary code remotely without user interaction, given network access. The vulnerability affects multiple Windows 10 21H2 builds prior to the patched versions listed. Microsoft has published an official security update to remediate this issue, as detailed in their security advisory.
Potential Impact
Successful exploitation of this vulnerability could allow an unauthorized attacker to execute arbitrary code remotely on affected Windows 10 21H2 systems. This could lead to full system compromise, including confidentiality, integrity, and availability impacts. The CVSS score of 8.1 reflects the high impact potential of this vulnerability.
Mitigation Recommendations
Microsoft has released an official fix for this vulnerability. Users and administrators should apply the security updates provided by Microsoft for Windows 10 Version 21H2 to remediate this issue. No additional mitigation steps are required beyond applying the official patch.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- microsoft
- Date Reserved
- 2026-09-01T01:16:35.984Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- official-fix
- Vendor Advisory Urls
- [{"url":"https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83997","vendor":"Microsoft"}]
Threat ID: 6aa0457bacd9273b49fbdf6d
Added to database: 09/08/2026, 17:27:23 UTC
Last enriched: 10/14/2026, 22:14:12 UTC
Last updated: 10/23/2026, 15:10:15 UTC
Views: 44
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