Microsoft Windows Graphics Kernel: Elevation of privilege via heap-based buffer overflow
Summary
A heap-based buffer overflow in the Windows Graphics Kernel allows an authorized local user with low privileges to elevate privileges on the affected system. Microsoft rates exploitation as high complexity and requires that the affected virtual machine has multiple assigned graphics adapters with differing configurations. An attacker therefore needs prior code execution or a logon on the machine. CVSS base score is 7.8; Microsoft reports no public exploitation at release.
Affected
- Windows 10 Version 1809 (before 10.0.17763.9487)
- Windows 10 Version 21H2 (before 10.0.19044.7846)
- Windows 10 Version 22H2 (before 10.0.19045.7846)
- Windows 11 Version 23H2 (before 10.0.22631.7711)
- Windows 11 Version 24H2 (before 10.0.26100.9974)
- Windows 11 Version 25H2 (before 10.0.26200.9974)
- Windows 11 Version 26H1 (before 10.0.28000.3501)
- Windows 11 Version 26H2 (before 10.0.26300.9974)
- Windows Server 2019 incl. Server Core (before 10.0.17763.9487)
- Windows Server 2022 (before 10.0.20348.5870)
- Windows Server 2025 incl. Server Core (before 10.0.26100.33822)
Fixed in
- November 2026 Windows security update (cumulative update) for each affected branch.
- Fixed builds as listed in the CVE record; confirm the exact build for your branch on MSRC.
Workaround
- No vendor workaround; patching is the fix.
- Until patched, review VMs with multiple virtual graphics adapters and remove extra or mismatched adapters where they are not needed (third-party suggestion by Action1).
- Limit local logon to these guests.
Exploitation
- No public exploitation reported at release.
- CVSS temporal exploit maturity: Unproven (E:U).
- Exploited in the wild: Unknown.
- No public proof of concept confirmed for this CVE.
Our recommendation
- Install the November 2026 Windows update on all affected systems, prioritising multi-user servers, RDS/VDI hosts and VMs.
- Inventory VMs with multiple virtual graphics adapters and review their configuration.
- Confirm fixed builds for your exact Windows branch on MSRC before rollout.
- Monitor NVD analysis and the CISA KEV catalogue for changes.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Critical
- Impact
- Elevation of privilege – Windows Graphics Kernel
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5131085, KB5131096, KB5131090, KB5131087, KB5132061, KB5132043
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Response Center: CVE-2026-125137 msrc.microsoft.com
- CVE Record CVE-2026-125137 www.cve.org
- Action1: Patch Tuesday November 2026 www.action1.com
- Cryptika: Microsoft November 2026 Patch Tuesday www.cryptika.com
- Strix: CVE-2026-125137 (third party) www.strix.ai
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, 03:24.
Original description (NVD)
Heap-based buffer overflow in Windows Graphics Kernel 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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