CVE-2026-119391: Microsoft Windows Hyper-V use-after-free privilege escalation

CVE-2026-119391 · Severity: high · CVSS 7.8 · Published 2026-11-10

Windows Hyper-V is Microsoft's virtualization platform used to run multiple isolated virtual machines on a single server. An authorized attacker with local access to a system can exploit a use-after-free vulnerability in Hyper-V to gain elevated system privileges, potentially compromising the entire host and all virtual machines running on it.

Technologies: Microsoft Windows Hyper-V. Vendors: Microsoft.

Quick answers

Is CVE-2026-119391 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-119391 being exploited in the wild.
How severe is CVE-2026-119391?
High severity, with a CVSS score of 7.8, published 10 November 2026.
Which products and versions are affected?
Microsoft Windows Hyper-V.
Is there a fix for CVE-2026-119391?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-119391 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-2026-119391?
Check whether you run Microsoft Windows Hyper-V. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A use-after-free vulnerability exists in Windows Hyper-V that can be triggered by an authorized attacker with local network or physical access. The vulnerability allows elevation of privileges through memory corruption in the hypervisor, bypassing security boundaries between virtual machines or between user and kernel mode.

Affected products

  • Microsoft Windows Hyper-V

Timeline

  • 2026-11-10: disclosed

References

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