Microsoft Windows: Local privilege escalation via out-of-bounds read in Spaceport.sys
Summary
An out-of-bounds read (CWE-125) in the Windows driver Spaceport.sys allows a local attacker with low privileges to elevate privileges on the affected host. The attacker must already have a user session on the system, for example through phishing, malware or a stolen account. Successful exploitation gives the attacker full control of the local machine (high confidentiality, integrity and availability impact).
Affected
- Windows 10 Version 1809 and Windows Server 2019 (incl. Server Core): before 10.0.17763.9376
- Windows 10 Version 21H2: before 10.0.19044.7807
- Windows 10 Version 22H2: before 10.0.19045.7807
- Windows 11 Version 23H2: before 10.0.22631.7652
- Windows 11 Version 24H2: before 10.0.26100.9711
- Windows 11 Version 25H2: before 10.0.26200.9711
- Windows 11 Version 26H1: before 10.0.28000.3231
- Windows 11 Version 26H2: before 10.0.26300.9711
- Windows Server 2022: before 10.0.20348.5761
- Windows Server 2025 (incl. Server Core): before 10.0.26100.33650
Fixed in
- Install the Microsoft security update for the affected build (builds listed under 'affected' are fixed from the stated version onward).
- For Windows 10 1809 and Server 2019, the October 2026 cumulative update is reported as KB5126651; confirm the mapping on MSRC before rollout.
Workaround
Unknown.
Exploitation
- No evidence of exploitation in the wild found.
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
- No public proof of concept found; this is not a confirmation that none exists.
Our recommendation
- Apply the Microsoft security update for all affected Windows 10, Windows 11 and Windows Server systems on the normal patch cycle.
- Prioritize multi-user systems, terminal servers and hosts where untrusted users or malware could run.
- Check whether Windows 10 1809 devices are still supported by Microsoft's lifecycle policy.
- Verify installed builds with winver or inventory tools after patching.
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)
- KB5126651, KB5126655, KB5126657, KB5126646, KB5127648, KB5126653
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Microsoft Security Update Guide: CVE-2026-83832 msrc.microsoft.com
- OpenCVE: CVE-2026-83832 app.opencve.io
- Vulners NVD: CVE-2026-83832 vulners.com
- Vulners CVELIST: CVE-2026-83832 vulners.com
- Vulners MSCVE: MS:CVE-2026-83832 vulners.com
- Strix: CVE-2026-83832 www.strix.ai
- Tenable Nessus plugin 365467 www.tenable.com
- VulDB: CVE-2026-83832 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, 02:57.
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.
Affected? We can help.
We check whether your systems are affected, install updates and close the gap – continuously with the System Health Checker if you wish.