---
id: CVE-2026-87705
title: >-
  Improper verification of source of a communication channel in Windows Hyper-V
  allows an unauthorized attacker to bypass a security feature over an adjacent
  network.
summary: >-
  Improper verification of source of a communication channel in Windows Hyper-V
  allows an unauthorized attacker to bypass a security feature over an adjacent
  network.
severity: high
cvss: 7.4
cvssVector: 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N'
cwe:
  - CWE-940
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T21:19:38.580'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-87705'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87705'
    label: secure@microsoft.com
tags:
  - nvd
ingestedAt: '2026-10-13T19:43:29.203Z'
---

## Overview

Improper verification of source of a communication channel in Windows Hyper-V allows an unauthorized attacker to bypass a security feature over an adjacent network.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.