Microsoft Windows Kernel: Security feature bypass through improper access control
Summary
A flaw in the Windows kernel (CWE-863, improper authorization) allows an authorized local attacker to bypass a security feature. The attacker needs a valid low-privilege account on the affected machine, and no user interaction is required. The impact is high for confidentiality and integrity, with no direct availability impact.
Affected
- Windows 10 Version 1607 (builds before 10.0.14393.9688)
- Windows 10 Version 1809 (builds before 10.0.17763.9487)
- Windows 10 Version 21H2 (builds before 10.0.19044.7846)
- Windows 10 Version 22H2 (builds before 10.0.19045.7846)
- Windows 11 Version 23H2 (builds before 10.0.22631.7711)
- Windows 11 Version 24H2 (builds before 10.0.26100.9974)
- Windows 11 Version 25H2 (builds before 10.0.26200.9974)
- Windows 11 Version 26H1 (builds before 10.0.28000.3501)
- Windows 11 Version 26H2 (builds before 10.0.26300.9974)
- Windows Server 2016 incl. Server Core (builds before 10.0.14393.9688)
- Windows Server 2019 incl. Server Core (builds before 10.0.17763.9487)
- Windows Server 2022 (builds before 10.0.20348.5870)
- Windows 11 Version 22H2: Unknown.
- Windows Server 2025: listed only by a secondary source (builds before 10.0.26100.33822), not confirmed by the CVE record.
Fixed in
Fixed in the Microsoft security update of November 2026. The fixed builds are the versions listed under affected. The KB number for this CVE is unknown; check the MSRC advisory for the exact update per product.
Workaround
Unknown. No vendor-documented workaround or mitigation has been identified. Patching is the only known fix.
Exploitation
- No evidence of in-the-wild exploitation or public proof of concept found; this means nothing is known, not that exploitation is ruled out.
- CVSS temporal vector E:U (exploit code maturity unproven).
- CISA SSVC: exploitation none, automatable no, technical impact total.
- NVD analysis was still pending at the time of research.
Our recommendation
- Install the November 2026 Windows security update on all affected systems, prioritising multi-user servers, Remote Desktop/terminal servers and shared workstations.
- Verify the installed build against the fixed builds listed above and the MSRC advisory.
- Limit local logons to trusted users and review accounts with local access, especially for contractors.
- Monitor for unusual local privilege or security feature changes on critical hosts.
- Recheck MSRC and NVD in a few days for updated information.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Security feature bypass – Windows Kernel
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5131291, KB5131085, KB5131096, KB5131090, KB5131087, KB5132061
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-112973 msrc.microsoft.com
- CVE Record CVE-2026-112973 (CVE.org) www.cve.org
- strix.ai: CVE-2026-112973 www.strix.ai
- Senserva: KB5131090 (Server 2022 November 2026 update, unconfirmed mapping) senserva.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 11 Nov 2026, 07:13.
Original description (NVD)
Improper access control in Windows Kernel allows an authorized attacker to bypass a security feature locally.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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