Microsoft Windows: Elevation of privilege in Windows Resource Management (MRM)
Summary
An integer overflow or wraparound in the Windows Resource Management (MRM) component allows an authorized local user to elevate privileges. The attacker needs an existing low-privileged account on the affected system and no user interaction is required. Impact on confidentiality, integrity and availability is rated high by NVD (CVSS 3.1: 7.8).
Affected
- Windows 10 Version 1607 (below 10.0.14393.9612)
- Windows 10 Version 1809 (below 10.0.17763.9376)
- Windows 10 Version 21H2 (below 10.0.19044.7807)
- Windows 10 Version 22H2 (below 10.0.19045.7807)
- Windows 11 Version 23H2 (below 10.0.22631.7652)
- Windows 11 Version 24H2 (below 10.0.26100.9711)
- Windows 11 Version 25H2 (below 10.0.26200.9711)
- Windows 11 Version 26H1 (below 10.0.28000.3231)
- Windows 11 Version 26H2 (below 10.0.26300.9711)
- Windows Server 2012 and Server Core installation (below 6.2.9200.26434)
- Windows Server 2012 R2 and Server Core installation (below 6.3.9600.23470)
- Windows Server 2016 (below 10.0.14393.9612)
Fixed in
- Fixed in the October 2026 Patch Tuesday update for the listed builds (see vendor advisory).
- Windows 10 Version 1607 and Windows Server 2012/2016: no specific KB number identified in the sources; verify on MSRC before rollout.
- Restart the system after installing the update.
Workaround
- Unknown. No vendor workaround was identified in the sources.
- General practice, not vendor guidance: limit local logon to trusted accounts and restrict who can run code on affected hosts.
Exploitation
- CISA SSVC: exploitation none, not automatable, total technical impact.
- Not listed in the CISA KEV catalog.
- EPSS: unavailable.
- Exploit code maturity listed as unproven by a third-party mirror of the advisory.
- No public proof of concept found in the research; this does not rule out that one exists.
Our recommendation
- Prioritise legacy Windows 10 Version 1607 and older Windows Server systems: check whether a patch or Extended Security Updates are available for your edition.
- Apply the October 2026 Microsoft update to all affected systems and restart them.
- Restrict local logon and code execution on shared, terminal and server systems until patched.
- Re-check CISA KEV and public exploit sources in the coming weeks.
Information from Microsoft (Patch Tuesday October 2026)
- Severity (Microsoft)
- Important
- Impact
- Elevation of privilege – Windows Resource Management (MRM)
- 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-2026-87702 msrc.microsoft.com
- Vulners: CVE-2026-87702 (CNA data) vulners.com
- OpenCVE: CVE-2026-87702 app.opencve.io
- Strix: CVE-2026-87702 www.strix.ai
- OffSeq Radar: CVE-2026-87702 radar.offseq.com
- IMFHT intel: CVE-2026-87702 (exploit maturity) cve.imfht.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, 01:34.
Original description (NVD)
Integer overflow or wraparound in Windows Resource Management (MRM) 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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