Windows DWM Core Library: Out-of-bounds read enables local privilege escalation
Summary
An out-of-bounds read (CWE-125) in the Windows Desktop Window Manager (DWM) Core Library allows an authorized local user to elevate privileges. Exploitation requires local access and a valid low-privilege account, so it is typically a second step after another compromise. Microsoft rates the flaw at CVSS 7.8 (High), while CISA SSVC rates it as not automatable.
Affected
- Windows 10 Version 1809 (10.0.17763.0 to below 10.0.17763.9376)
- Windows 10 Version 21H2 (below 10.0.19044.7807)
- Windows 10 Version 22H2 (below 10.0.19045.7807, verify on MSRC)
- Windows 11 Versions 23H2 (below 10.0.22631.7652), 24H2 (below 10.0.26100.9711), 25H2 (below 10.0.26200.9711) and 26H2 (below 10.0.26300.9711)
- Windows Server 2019, including Server Core (below 10.0.17763.9376)
- Windows Server 2022 (below 10.0.20348.5761)
- Windows Server 2025, including Server Core (below 10.0.26100.33650)
Fixed in
- Install the Windows security update released on October 13, 2026 for each affected version.
- Fixed build for Windows 10 1809 and Server 2019 per CNA record: 10.0.17763.9376 (verify on MSRC).
- KB number for Windows 10 1809 not confirmed.
Workaround
Unknown. No workaround was found; the security update is the fix.
Exploitation
- MSRC snapshot: not exploited, no publicly available exploit code.
- CISA SSVC: exploitation none, not automatable.
- Not listed in CISA KEV. EPSS about 0.003 (below 1%).
- No public PoC or in-the-wild exploitation found in research; keep monitoring.
Our recommendation
- Apply the October 2026 Windows security update to all affected systems, starting with multi-user systems such as terminal servers, shared servers and workstations used by several people.
- Confirm edition, build and support status. Windows 10 1809 is old; unsupported systems will not receive this fix and need upgrade planning.
- Restrict local logon rights and keep endpoint protection active to reduce the chance of an attacker first obtaining a low-privilege account.
- Verify version and KB data on the MSRC Security Update Guide before rollout.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows DWM Core Library
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5127648, KB5126651, KB5126655, KB5126657, KB5126646, KB5126653
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-88181 msrc.microsoft.com
- OpenCVE: CVE-2026-88181 app.opencve.io
- Vulners CVE list: CVE-2026-88181 vulners.com
- Strix: CVE-2026-88181 www.strix.ai
- Vulners VulnRichment: CVE-2026-88181 vulners.com
- VulDB: CVE-2026-88181 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 2 Nov 2026, 01:14.
Original description (NVD)
Out-of-bounds read in Windows DWM Core Library 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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