Microsoft Windows: Information disclosure in Windows Overlay Filter
Summary
A local information disclosure flaw in the Windows Overlay Filter component allows an authenticated low-privilege user to read sensitive system information. Microsoft describes the disclosed data as kernel memory read from a user-mode process. The attack requires local access and no user interaction, so the main risk is a malicious or compromised local account, or an attacker who already has a foothold through another vulnerability.
Affected
- Windows 10 Version 1607 (before 10.0.14393.9688)
- 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 2016, including Server Core (before 10.0.14393.9688)
- Windows Server 2019, including Server Core (before 10.0.17763.9487)
- Windows Server 2022 (before 10.0.20348.5870)
Fixed in
- Installation of the November 2026 cumulative updates (Microsoft Patch Tuesday, 10 November 2026) for the builds listed above.
- Exact KB article per product: see the MSRC Security Update Guide.
Workaround
Unknown.
Exploitation
- Microsoft assessment: not publicly disclosed, not exploited, exploitation less likely.
- CISA SSVC: exploitation none, automatable no, technical impact partial.
- No public proof-of-concept exploit found.
- Not listed in CISA KEV.
Our recommendation
- Inventory Windows systems and compare builds with the fixed versions above.
- Install the November 2026 cumulative updates in the standard monthly patch cycle, prioritising multi-user terminal servers and shared workstations.
- Check the support status of Windows 10 1607 and 1809 systems, as updates for these branches are only available while they are supported.
- Re-check the MSRC and NVD entries in case the exploitability rating changes.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Information disclosure – Windows Overlay Filter
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5131291, KB5131085, KB5131096, KB5131090, KB5131087, KB5132061
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft MSRC Security Update Guide msrc.microsoft.com
- CVE Record CVE-2026-108409 www.cve.org
- Strix CVE-2026-108409 www.strix.ai
- OffSeq Radar CVE-2026-108409 radar.offseq.com
- Senserva KB 5131080 senserva.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, 16:57.
Original description (NVD)
Exposure of sensitive system information to an unauthorized control sphere in Windows Overlay Filter allows an authorized attacker to disclose information 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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