Description
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.
Affected products
microsoft: windows 10 1607; microsoft: windows 10 1809; microsoft: windows 10 21h2; microsoft: windows 10 22h2; microsoft: windows 11 23h2; microsoft: windows 11 24h2; microsoft: windows 11 25h2; microsoft: windows 11 26h1; microsoft: windows 11 26h2; microsoft: windows server 2012; microsoft: windows server 2016; microsoft: windows server 2019; microsoft: windows server 2022; microsoft: windows server 2025
References1
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-87705 PatchVendor Advisory
Metrics
- CVSS 3.1
-
7.4
HIGH
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 38 · as of 11 November 2026
- CWE
- CWE-940
Could this be exploited in your environment?
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