Microsoft Windows Local Session Manager: Elevation of privilege via use after free
Summary
A use-after-free flaw in the Windows Local Session Manager (LSM) allows an authorized local user to elevate privileges on the affected system. Exploitation requires a local foothold, such as a low-privilege account or malware running as a standard user, and high attack complexity. Microsoft rates the impact as high for confidentiality, integrity and availability. The CVE record lists no known exploitation and no public proof-of-concept code at the time of writing.
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 (version range not fully confirmed)
- 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
- Install the November 2026 cumulative update for the affected Windows version (released 2026-11-10).
- Fixed builds are listed under Affected. KB mapping: Unknown. Verify in the MSRC Security Update Guide.
Workaround
Unknown. No vendor workaround was found; applying the update is the fix.
Exploitation
- Exploited in the wild: No evidence found.
- Public proof-of-concept: None found.
- CISA SSVC: Exploitation none, automatable no, technical impact total.
Our recommendation
- Patch affected Windows 10, 11 and Server systems in the November 2026 update cycle, prioritising multi-user systems, Remote Desktop and terminal servers, and jump hosts.
- Verify the KB number in the MSRC Security Update Guide or Microsoft Update Catalog before deployment.
- Reduce local EoP risk by limiting local administrator rights and using application control such as WDAC or AppLocker.
- Check whether any affected Windows 10 builds are past Microsoft's support lifecycle.
- Re-check CISA KEV and the MSRC exploitation status once NVD analysis is complete.
Information from Microsoft (Patch Tuesday November 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Local Session Manager (LSM)
- 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
- MSRC Security Update Guide msrc.microsoft.com
- CVE.org CVE Record www.cve.org
- Strix CVE-2026-95876 (unverified) www.strix.ai
- Action1 Patch Tuesday November 2026 www.action1.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, 08:05.
Original description (NVD)
Use after free in Windows Local Session Manager (LSM) 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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