Microsoft Windows Installer: Elevation of privilege via use-after-free
Summary
A use-after-free flaw in the Windows Installer component allows an authorized local attacker to elevate privileges. The CNA record lists Windows 10 1607, Windows Server 2016, several newer Windows 10 and 11 builds, and Windows Server 2012 and 2012 R2. Exploitation requires local access with low privileges and high attack complexity, with a CVSS 3.1 base score of 7.0 (High). Remote exploitation is not described.
Affected
- Windows 10 Version 1607: builds below 10.0.14393.0 to 10.0.14393.9612 (per CNA record)
- Windows Server 2016: builds 10.0.14393.0 to below 10.0.14393.9612 (per CNA record)
- Also listed: Windows 10 1809, 21H2, 22H2; Windows 11 23H2, 24H2, 25H2, 26H1, 26H2; Windows Server 2012 and 2012 R2 (including Server Core)
- The NVD CPE lists only Windows 10 1607, so the affected list is incomplete there.
Fixed in
- Windows 10 1607 and Windows Server 2016: build 10.0.14393.9612 or later (per CNA record, verify on MSRC)
- Other fixed builds: see the MSRC advisory
- KB article number for 1607: Unknown.
Workaround
- No vendor workaround found.
- Unknown whether an interim configuration change reduces exposure.
- Limiting who can run installers and using least-privilege accounts is general hardening, not a documented fix for this CVE.
Exploitation
- CISA SSVC: exploitation none, automatable no, technical impact total.
- Not listed in CISA KEV at the time of research.
- EPSS about 0.0025.
- No public proof of concept found; recheck before making a final decision.
Our recommendation
- Identify Windows 10 1607 and Windows Server 2016 systems and confirm their support status.
- Deploy the update from the MSRC advisory where it is available.
- Where the build is unsupported, plan a replacement or isolate the system.
- Check which CVE ID your scanner reports, as CVE-2026-108468 may cover the same flaw with different builds.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Installer
- Status on Patch Tuesday
- Neither exploited nor publicly disclosed
- Exploitability assessment
- Exploitation less likely
- Product family
- Windows, Windows ESU (Extended Security Updates)
- Updates (KB)
- KB5126651, KB5126655, KB5126657, KB5126646, KB5127648, KB5126653
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Response Center: CVE-2026-83752 msrc.microsoft.com
- Vulners: CVELIST CVE-2026-83752 vulners.com
- Vulners: NVD CVE-2026-83752 vulners.com
- Strix: CVE-2026-83752 www.strix.ai
- OpenCVE: CVE-2026-83752 app.opencve.io
- BDU FSTEC: BDU:2026-16731 (related Windows Installer entry) vulners.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 4 Nov 2026, 08:17.
Original description (NVD)
Use after free in Windows Installer 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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