Windows Storage: Stack-based buffer overflow allows local privilege escalation
Summary
A stack-based buffer overflow in the Windows Storage component of several Windows 10, Windows 11 and Windows Server versions allows an attacker to elevate privileges locally. The attacker needs a valid local account or an existing foothold on the system. Successful exploitation would affect confidentiality, integrity and availability of the system, but the attack is complex and requires local access.
Affected
- Windows 10 Version 1809 (before 10.0.17763.9376)
- Windows 10 Version 21H2 (before 10.0.19044.7807)
- Windows 10 Version 22H2 (before 10.0.19045.7807)
- Windows 11 Version 23H2 (before 10.0.22631.7652)
- Windows 11 Version 24H2 (before 10.0.26100.9711)
- Windows 11 Version 25H2 (before 10.0.26200.9711)
- Windows 11 Version 26H1 (before 10.0.28000.3231)
- Windows 11 Version 26H2 (before 10.0.26300.9711)
- Windows Server 2019, including Server Core (before 10.0.17763.9376)
- Windows Server 2022 (before 10.0.20348.5761)
- Windows Server 2025, including Server Core (before 10.0.26100.33650)
Fixed in
- Windows 10 Version 1809 and Windows Server 2019: 10.0.17763.9376 or later
- Windows 10 Version 21H2: 10.0.19044.7807 or later
- Windows 10 Version 22H2: 10.0.19045.7807 or later
- Windows 11 23H2: 10.0.22631.7652 or later
- Windows 11 24H2, 25H2 and 26H2: 9711 build or later as listed by the CNA
- Windows 11 26H1: 10.0.28000.3231 or later
- Windows Server 2022: 10.0.20348.5761 or later
- Windows Server 2025: 10.0.26100.33650 or later
- Cumulative update of October 2026 (KB5126651 for Windows 10 1809 and Server 2019 according to third-party sources)
Workaround
Unknown. No vendor workaround identified. Install the security update.
Exploitation
- CISA SSVC: exploitation none, not automatable, total technical impact
- Exploitation in the wild: Unknown
- Public proof of concept: none found
- EPSS about 0.0029 (low predicted exploitation probability)
Our recommendation
- Install the October 2026 security update on affected systems, starting with servers and shared or multi-user systems.
- Plan migration away from Windows 10 Version 1809 and Windows Server 2019 where possible, as these are older platforms.
- Restrict local logon and user privileges, and monitor systems for privilege escalation.
- Verify the fixed builds in the MSRC Security Update Guide before rollout.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Storage
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation unlikely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5126651, KB5126657, KB5126655, KB5126653, KB5127648, KB5126646
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft MSRC Security Update Guide msrc.microsoft.com
- Vulners CVE record (CVELIST) vulners.com
- Vulners NVD record vulners.com
- Positive Technologies PT-2026-111891 vulners.com
- Tenable Nessus plugin 365473 www.tenable.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 4 Nov 2026, 10:01.
Original description (NVD)
Stack-based buffer overflow in Windows Storage allows an authorized attacker to elevate privileges 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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