Microsoft Windows NTFS: Heap-Based Buffer Overflow Allows Local Privilege Escalation

Summary

A heap-based buffer overflow in the Windows NTFS file system component allows an authorized local user to elevate privileges. An attacker who already has a low-privilege account on the system, for example through phishing or stolen credentials, could gain SYSTEM rights. The flaw cannot be exploited remotely. Microsoft has released fixes for the affected builds.

Affected

• Windows 10 Version 1607 (10.0.14393.0 to before 10.0.14393.9612)
• Windows 10 Version 1809 (10.0.17763.0 to before 10.0.17763.9376)
• Windows 10 Version 21H2 (10.0.19044.0 to before 10.0.19044.7807)
• Windows 10 Version 22H2 (10.0.19045.0 to before 10.0.19045.7807)
• Windows 11 Version 23H2 (10.0.22631.0 to before 10.0.22631.7652)
• Windows 11 Version 24H2 (10.0.26100.0 to before 10.0.26100.9711)
• Windows 11 Version 25H2 (10.0.26200.0 to before 10.0.26200.9711)
• Windows 11 Version 26H1 (10.0.28000.0 to before 10.0.28000.3231)
• Windows 11 Version 26H2 (10.0.26300.0 to before 10.0.26300.9711)
• Windows Server 2016, including Server Core (10.0.14393.0 to before 10.0.14393.9612)
• Windows Server 2019, including Server Core (10.0.17763.0 to before 10.0.17763.9376)
• Windows Server 2022 (10.0.20348.0 to before 10.0.20348.5761)

Fixed in

• Windows 10 1607 and Windows Server 2016: 10.0.14393.9612 or later
• Windows 10 1809 and Windows Server 2019: 10.0.17763.9376 or later
• Windows 10 21H2: 10.0.19044.7807 or later
• Windows 10 22H2: 10.0.19045.7807 or later
• Windows 11 23H2: 10.0.22631.7652 or later
• Windows 11 24H2: 10.0.26100.9711 or later
• Windows 11 25H2 and 26H2: 10.0.26200.9711 or later (26H2: 10.0.26300.9711 or later)
• Windows 11 26H1: 10.0.28000.3231 or later
• Windows Server 2022: 10.0.20348.5761 or later
• Verify the exact update numbers for each system on the Microsoft Security Update Guide.

Workaround

Unknown. No workaround was identified; installing the security update is the fix.

Exploitation

• No evidence of exploitation in the wild was found in the sources reviewed.
• No public proof-of-concept exploit was found.
• CISA SSVC assessment: exploitation none, not automatable, total technical impact.
• EPSS score is low (0.00341).

Our recommendation

• Install the October 2026 cumulative security updates on all affected Windows systems, starting with servers and shared or terminal servers.
• Replace or retire Windows 10 1607 and 1809 systems if they are out of support or cannot be patched.
• Limit local logon rights and restrict who can write to shared NTFS volumes until patching is complete.
• Verify the installed build numbers after patching and monitor for unusual privilege changes.

Public exploits iAttack code is publicly available (PoC on GitHub, Metasploit or Exploit-DB).

PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.

Research sources

• Microsoft Security Update Guide: CVE-2026-70010 msrc.microsoft.com
• Vulners MSCVE: MS:CVE-2026-70010 vulners.com
• Vulners NVD: NVD:CVE-2026-70010 vulners.com
• OpenCVE: CVE-2026-70010 app.opencve.io
• Strix: CVE-2026-70010 www.strix.ai
• Positive Technologies advisory PT-2026-112159 vulners.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 2 Nov 2026, 04:32.