---
id: "CVE-2026-118737"
page: "https://infrastack.ai/live/CVE-2026-118737"
kind: "vulnerability"
aliases: ["CVE-2026-118737"]
title: "Windows RPC Runtime: improper signature verification allows remote code execution (November 2026 Patch Tuesday)"
severity: "high"
cvss: 8.1
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "Windows 10 1607 / Server 2016", "fixed": ["10.0.14393.9688"], "affected": ">= 10.0.14393.0, < 10.0.14393.9688", "ecosystem": "microsoft"}, {"name": "Windows 10 1809 / Server 2019", "fixed": ["10.0.17763.9487"], "affected": ">= 10.0.17763.0, < 10.0.17763.9487", "ecosystem": "microsoft"}, {"name": "Windows 10 21H2", "fixed": ["10.0.19044.7846"], "affected": ">= 10.0.19044.0, < 10.0.19044.7846", "ecosystem": "microsoft"}, {"name": "Windows 10 22H2", "fixed": ["10.0.19045.7846"], "affected": ">= 10.0.19045.0, < 10.0.19045.7846", "ecosystem": "microsoft"}, {"name": "Windows 11 23H2", "fixed": ["10.0.22631.7711"], "affected": ">= 10.0.22631.0, < 10.0.22631.7711", "ecosystem": "microsoft"}, {"name": "Windows 11 24H2", "fixed": ["10.0.26100.9974"], "affected": ">= 10.0.26100.0, < 10.0.26100.9974", "ecosystem": "microsoft"}, {"name": "Windows 11 25H2", "fixed": ["10.0.26200.9974"], "affected": ">= 10.0.26200.0, < 10.0.26200.9974", "ecosystem": "microsoft"}, {"name": "Windows 11 26H1", "fixed": ["10.0.28000.3501"], "affected": ">= 10.0.28000.0, < 10.0.28000.3501", "ecosystem": "microsoft"}, {"name": "Windows 11 26H2", "fixed": ["10.0.26300.9974"], "affected": ">= 10.0.26300.0, < 10.0.26300.9974", "ecosystem": "microsoft"}, {"name": "Windows Server 2022", "fixed": ["10.0.20348.5870"], "affected": ">= 10.0.20348.0, < 10.0.20348.5870", "ecosystem": "microsoft"}, {"name": "Windows Server 2025", "fixed": ["10.0.26100.33822"], "affected": ">= 10.0.26100.0, < 10.0.26100.33822", "ecosystem": "microsoft"}]
ecosystems: []
tags: ["infrastructure", "microsoft", "rpc", "windows", "windows-server"]
not_affected_if: []
published_at: "2026-11-10T19:19:50+00:00"
first_seen_at: "2026-11-10T19:24:55+00:00"
updated_at: "2026-11-10T23:00:51+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-118737", "first_seen_at": "2026-11-10T19:24:55+00:00"}, {"source": "analyst", "url": "https://nvd.nist.gov/vuln/detail/cve-2026-118737", "first_seen_at": "2026-11-10T23:00:51+00:00", "cites": ["https://nvd.nist.gov/vuln/detail/cve-2026-118737", "https://www.zerodayinitiative.com/blog/2026/11/10/the-november-2026-security-update-review"]}]
exploit_sources: []
---

# Windows RPC Runtime: improper signature verification allows remote code execution (November 2026 Patch Tuesday)

Link for people: https://infrastack.ai/live/CVE-2026-118737 (this .md is for agents)

The Windows Remote Procedure Call runtime does not properly verify a cryptographic signature. An unauthenticated attacker on the network can execute code on an affected Windows machine.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- microsoft:Windows 10 1607 / Server 2016 affected >= 10.0.14393.0, < 10.0.14393.9688 fixed 10.0.14393.9688
- microsoft:Windows 10 1809 / Server 2019 affected >= 10.0.17763.0, < 10.0.17763.9487 fixed 10.0.17763.9487
- microsoft:Windows 10 21H2 affected >= 10.0.19044.0, < 10.0.19044.7846 fixed 10.0.19044.7846
- microsoft:Windows 10 22H2 affected >= 10.0.19045.0, < 10.0.19045.7846 fixed 10.0.19045.7846
- microsoft:Windows 11 23H2 affected >= 10.0.22631.0, < 10.0.22631.7711 fixed 10.0.22631.7711
- microsoft:Windows 11 24H2 affected >= 10.0.26100.0, < 10.0.26100.9974 fixed 10.0.26100.9974
- microsoft:Windows 11 25H2 affected >= 10.0.26200.0, < 10.0.26200.9974 fixed 10.0.26200.9974
- microsoft:Windows 11 26H1 affected >= 10.0.28000.0, < 10.0.28000.3501 fixed 10.0.28000.3501
- microsoft:Windows 11 26H2 affected >= 10.0.26300.0, < 10.0.26300.9974 fixed 10.0.26300.9974
- microsoft:Windows Server 2022 affected >= 10.0.20348.0, < 10.0.20348.5870 fixed 10.0.20348.5870
- microsoft:Windows Server 2025 affected >= 10.0.26100.0, < 10.0.26100.33822 fixed 10.0.26100.33822

## How to check

Run winver or PowerShell [System.Environment]::OSVersion.Version / (Get-ItemProperty 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion').UBR and compare the full build (e.g. 10.0.26100.xxxx) to the fixed build for your release. Below the fixed build means affected.

## Fix

Install the November 2026 cumulative update so the OS build reaches: Win10 1607/Server 2016 10.0.14393.9688; 1809/Server 2019 10.0.17763.9487; Win10 21H2 10.0.19044.7846; 22H2 10.0.19045.7846; Win11 23H2 10.0.22631.7711; Win11 24H2 10.0.26100.9974; 25H2 10.0.26200.9974; 26H1 10.0.28000.3501; 26H2 10.0.26300.9974; Server 2022 10.0.20348.5870; Server 2025 10.0.26100.33822. KB numbers: see the MSRC page.

## Timeline

- 2026-11-10T19:24:55+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-118737
- 2026-11-10T23:00:51+00:00 analyst https://nvd.nist.gov/vuln/detail/cve-2026-118737 — Microsoft's CNA record (via NVD) gives affected builds and fixed builds; MSRC page is JS-only and unreadable here, so KB numbers unknown and nothing marked verified. No exploitation or PoC found; CVSS 8.1, AC:H, PR:N.

## Documents

- [advisory] NVD: CVE-2026-118737 (Microsoft CNA data) https://nvd.nist.gov/vuln/detail/cve-2026-118737
- [mentions] ZDI: The November 2026 Security Update Review https://www.zerodayinitiative.com/blog/2026/11/10/the-november-2026-security-update-review

## From the sources

Improper verification of cryptographic signature in Windows Remote Procedure Call Runtime allows an unauthorized attacker to execute code over a network.

---

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