Windows NTFS: Elevation of privilege through sandbox escape
Summary
A local elevation of privilege vulnerability in the Windows NTFS file system allows sandboxed processes to create reparse points and escape the sandbox. An attacker who is already logged on and can run a crafted application may gain elevated privileges with high impact on confidentiality, integrity and availability. Remote exploitation is not described. The record has inconsistencies (CWE, product list), so the details must be verified on the MSRC advisory.
Affected
- Windows 10 Version 1607 (10.0.14393.0 before 10.0.14393.9688)
- Windows 10 Version 1809 (10.0.17763.0 before 10.0.17763.9487)
- Windows 10 Version 21H2 (10.0.19044.0 before 10.0.19044.7846)
- Windows 10 Version 22H2 (10.0.19045.0 before 10.0.19045.7846)
- Windows 11 Version 23H2 (10.0.22631.0 before 10.0.22631.7711)
- Windows 11 Version 24H2 (10.0.26100.0 before 10.0.26100.9974)
- Windows 11 Version 25H2 (10.0.26200.0 before 10.0.26200.9974)
- Windows 11 Version 26H1 (10.0.28000.0 before 10.0.28000.3501)
- Windows 11 Version 26H2 (10.0.26300.0 before 10.0.26300.9974)
- Windows Server 2016 incl. Server Core (10.0.14393.0 before 10.0.14393.9688)
- Windows Server 2019 incl. Server Core (10.0.17763.0 before 10.0.17763.9487)
- Windows Server 2022 (10.0.20348.0 before 10.0.20348.5870)
Note: third-party sources list a different subset; verify on MSRC.
Fixed in
- Security update per Microsoft; the fixed builds are the versions listed above.
- KB number: Unknown.
Workaround
- None known. The update is the mitigation.
- Until patched, limit local logon to trusted users, especially on shared terminal servers.
Exploitation
- Exploited in the wild: No (as reported by a third-party source).
- Public proof of concept: None found.
- Microsoft exploitability assessment: Unknown.
Our recommendation
- Check the MSRC advisory for the exact affected builds and KB numbers.
- Patch affected Windows 10, Windows 11 and Windows Server systems with the November 2026 updates.
- Prioritise shared workstations and terminal servers.
- Monitor for public proof of concept code or CISA KEV entries.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows NTFS
- 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-2026-100223 msrc.microsoft.com
- CVE Record: CVE-2026-100223 www.cve.org
- Senserva KB 5132061 senserva.com
- Senserva KB 5131096 senserva.com
- Strix CVE-2026-100223 www.strix.ai
- NVD CVE-2019-1170 (similar description) nvd.nist.gov
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, 04:42.
Original description (NVD)
An elevation of privilege vulnerability exists when reparse points are created by sandboxed processes allowing sandbox escape. An attacker who successfully exploited the vulnerability could use the sandbox escape to elevate privileges on an affected system. To exploit the vulnerability, an attacker would first have to log on to the system, and then run a specially crafted application to take control over the affected system. The security update addresses the vulnerability by preventing sandboxed processes from creating reparse points targeting inaccessible files.
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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