Windows Storage: Heap-based buffer overflow enables local privilege escalation
Summary
A heap-based buffer overflow (CWE-122) in the Windows Storage component allows an authorized local attacker to elevate privileges. The CNA rates the issue CVSS 3.1 7.0 (High). Exploitation requires a low-privileged account and local code execution or an existing foothold on the system, so the risk mainly arises after an initial compromise.
Affected
- 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 2022: 10.0.20348.0 to before 10.0.20348.5761
- Windows Server 2025 (including Server Core): 10.0.26100.0 to before 10.0.26100.33650
Fixed in
- October 2026 cumulative security update (13 October 2026)
- Fixed builds: 10.0.22631.7652 (23H2), 10.0.26100.9711 (24H2), 10.0.26200.9711 (25H2), 10.0.28000.3231 (26H1), 10.0.26300.9711 (26H2), 10.0.20348.5761 (Server 2022), 10.0.26100.33650 (Server 2025)
- Reported KB mapping (secondary source, unverified): KB5126653, KB5126646, KB5126655, KB5127646, KB5127648
Workaround
Unknown.
Exploitation
- CISA SSVC: exploitation none, not automatable, total technical impact
- No evidence of active exploitation found
- No public proof of concept found
- EPSS 0.00252 at the time of capture
- CISA KEV listing not verified
Our recommendation
- Install the October 2026 cumulative update on all affected Windows 11 and Windows Server systems
- Confirm the fixed builds and exploitability status on the Microsoft Security Update Guide, since the version data was taken from secondary sources
- Limit local logon and administrative rights on shared PCs and terminal servers
- Monitor for local privilege escalation indicators and re-check CISA KEV status periodically
Information from Microsoft (Patch Tuesday October 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-102189 msrc.microsoft.com
- Strix: CVE-2026-102189 (CNA affected products) www.strix.ai
- Vulners: NVD record CVE-2026-102189 (EPSS) vulners.com
- Vulners: Positive Technologies PT-2026-111901 (KB mapping) 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 4 Nov 2026, 09:56.
Original description (NVD)
Heap-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.
Affected? We can help.
We check whether your systems are affected, install updates and close the gap – continuously with the System Health Checker if you wish.