Windows Biometric Service: Elevation of privilege via heap-based buffer overflow
Summary
Microsoft Windows Biometric Service contains a heap-based buffer overflow (CWE-122) that allows an authorized, locally logged-on attacker to elevate privileges on the system. The attack requires local access and low privileges, so the main risk is a second step after a compromised user account or malware on a workstation. The CVSS 3.1 base score is 7.8 (High), with high impact on confidentiality, integrity and availability.
Affected
- Windows 10 Version 1607 (10.0.14393.0 before 10.0.14393.9512)
- Windows 10 Version 1809 (10.0.17763.0 before 10.0.17763.9245)
- Windows 10 Version 21H2 (10.0.19044.0 before 10.0.19044.7725)
- Windows 10 Version 22H2 (10.0.19045.0 before 10.0.19045.7725)
- Windows 11 Version 23H2 (10.0.22631.0 before 10.0.22631.7582)
- Windows 11 Version 24H2 (10.0.26100.0 before 10.0.26100.9445)
- Windows 11 Version 25H2 (10.0.26200.0 before 10.0.26200.9445)
- Windows 11 Version 26H1 (10.0.28000.0 before 10.0.28000.2954)
- Windows Server 2016 incl. Server Core (10.0.14393.0 before 10.0.14393.9512)
- Windows Server 2019 incl. Server Core (10.0.17763.0 before 10.0.17763.9245)
- Windows Server 2022 (10.0.20348.0 before 10.0.20348.5622)
- Windows Server 2025 (10.0.26100.0 before 10.0.26100.33438)
Fixed in
- Windows 10 1607 / Windows Server 2016: 10.0.14393.9512
- Windows 10 1809 / Windows Server 2019: 10.0.17763.9245
- Windows 10 21H2: 10.0.19044.7725
- Windows 10 22H2: 10.0.19045.7725
- Windows 11 23H2: 10.0.22631.7582
- Windows 11 24H2: 10.0.26100.9445
- Windows 11 25H2: 10.0.26200.9445
- Windows 11 26H1: 10.0.28000.2954
- Windows Server 2022: 10.0.20348.5622
- Windows Server 2025: 10.0.26100.33438
- KB article numbers: Unknown. Verify the build list against the MSRC advisory.
Workaround
Unknown. No workaround or mitigation was found in the sources reviewed; install the security update.
Exploitation
- No evidence of exploitation in the wild in the sources reviewed.
- Exploit maturity is Unproven (E:U). CISA SSVC: exploitation none, not automatable, total technical impact.
- No public proof of concept found.
- Not listed in the CISA KEV catalog in the sources reviewed.
Our recommendation
- Install the Windows security update from the Microsoft Security Update Guide on all affected systems, starting with shared workstations and servers with many user sessions.
- Check the product list and build numbers on the MSRC page before deployment.
- Identify Windows 10 1607 and 1809 systems, check whether they are still in use and whether extended support applies.
- Monitor for suspicious local privilege escalation and recheck NVD, CISA KEV and PoC sources once NVD analysis is complete.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Biometric Service
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5123099, KB5122876, KB5122878, KB5122882, KB5122880, KB5124008
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- CVE Record CVE-2026-96127 (CVE Program) www.cve.org
- Microsoft Security Update Guide: CVE-2026-96127 msrc.microsoft.com
- Strix CVE-2026-96127 (third-party mirror) www.strix.ai
- VulDB 401525 (related Biometric Service CVE, for comparison) vuldb.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, 02:32.
Original description (NVD)
Heap-based buffer overflow in Windows Biometric Service 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.
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