Windows Spaceport.sys: Out-of-bounds read leads to local privilege escalation
Summary
An out-of-bounds read in the Windows Spaceport.sys kernel-mode driver allows a local, authorized user to elevate privileges. An attacker needs a low-privileged account on the affected system, so the flaw is not directly reachable from the internet. A successful attack gives full control of the machine. Microsoft has published patches, and exploitation is not known.
Affected
- Windows 10 Version 1607 and Windows Server 2016 (builds 10.0.14393.0 to below 10.0.14393.9612)
- Windows 10 Version 1809 (builds 10.0.17763.0 to below 10.0.17763.9376)
- Windows 10 Version 21H2 (builds 10.0.19044.0 to below 10.0.19044.7807)
- Windows 10 Version 22H2 (builds 10.0.19045.0 to below 10.0.19045.7807)
- Windows 11 Versions 23H2 (builds 10.0.22631.0 to below 10.0.22631.7652), 24H2, 25H2, 26H1 and 26H2
- Windows Server 2012 and 2012 R2 (including Server Core installations)
Fixed in
- Patch via Windows Update or the Microsoft Update Catalog. Install the update that addresses CVE-2026-96862.
- First fixed builds per the CNA data: 10.0.14393.9612 (1607/Server 2016), 10.0.17763.9376 (1809), 10.0.19044.7807 (21H2), 10.0.19045.7807 (22H2), 10.0.22631.7652 (23H2), 10.0.26100.9711 (24H2).
- The build numbers were not confirmed on MSRC and must be verified there before rollout.
Workaround
No vendor workaround known. General hardening: enforce least-privilege policies so that standard users cannot load drivers or run privileged services.
Exploitation
- Exploited in the wild: no evidence found.
- CISA SSVC: exploitation none, not automatable, total technical impact.
- EPSS below 1%.
- No public proof of concept found.
- CISA KEV status not confirmed.
Our recommendation
- Install the Microsoft security update for CVE-2026-96862 on all affected systems, prioritizing shared terminals, RDS/Citrix hosts and systems where users are not fully trusted.
- Verify the fixed build numbers on the MSRC advisory before deployment.
- Check whether Windows 10 1607, Server 2016 or other older versions are still in use and still supported.
- Monitor for privilege escalation indicators on endpoints and servers.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Spaceport.sys
- 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 Response Center advisory msrc.microsoft.com
- OpenCVE CVE record app.opencve.io
- Vulners CNA data (version ranges) vulners.com
- Positive Technologies PT-2026-112598 vulners.com
- VulDB CVE-2026-96862 vuldb.com
- Strix CVE-2026-96862 (aggregator, use with caution) www.strix.ai
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, 00:47.
Original description (NVD)
Out-of-bounds read in Windows Spaceport.sys 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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