Windows 10 Version 1607: Use-after-free in Windows Installer allows privilege escalation
Summary
A use-after-free vulnerability (CWE-416) in Windows Installer, the component that installs, repairs and removes MSI packages, affects Windows 10 Version 1607 and Windows Server 2016. An authorized local attacker can exploit it to elevate privileges, potentially to SYSTEM. Exploitation requires winning a race condition and a local logon or an existing foothold on the system, so the vulnerability is not remotely exploitable. Microsoft marks it as not exploited at release.
Affected
- Microsoft Windows 10 Version 1607 (x64 and x86): builds below 10.0.14393.9612
- Microsoft Windows Server 2016: builds below 10.0.14393.9612
Fixed in
- Build 10.0.14393.9612 or later (per CNA data; KB number not confirmed, verify on the MSRC update guide)
- Support status of Windows 10 Version 1607 / LTSB 2016 must be verified with Microsoft before assuming a patch is available
Workaround
- Unknown. No vendor workaround was found in the sources.
Exploitation
- Not exploited at release (Microsoft).
- Exploitation requires winning a race condition (CVSS AC:H).
- CISA SSVC: exploitation none, automatable no, technical impact total.
- No public proof of concept or CISA KEV listing found; absence of evidence, not confirmation.
Our recommendation
- Check whether any Windows 10 Version 1607 or Server 2016 systems are in use; treat unsupported systems as a higher risk than this single CVE.
- Verify patch availability and support status with Microsoft; plan an upgrade if no patch is available.
- Restrict local interactive logon to trusted users and remove unnecessary local administrator rights.
- Monitor for unexpected installer activity and privilege changes on workstations and shared servers.
- Pay particular attention to chaining risks such as phishing payloads or malicious macros.
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)
- KB5126835, KB5126836, KB5126868, KB5126651, KB5126657, KB5126655
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-108468 msrc.microsoft.com
- Microsoft Security Update Guide (vulnerability page) msrc.microsoft.com
- Vulners: CVE List (CNA data) vulners.com
- Vulners: Microsoft CVE mirror vulners.com
- Vulners: NVD record 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, 09:41.
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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