Improper access control in Microsoft Windows and Windows Server - CVE-2026-105733
Published: October 13, 2026
Vulnerability identifier: #VU154351
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-105733
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to execute arbitrary code on the Hyper-V host operating system.
The vulnerability exists due to improper access control in Windows Hyper-V when running applications on a guest virtual machine. A local user can run a specially crafted application on the guest to execute arbitrary code on the Hyper-V host operating system.
In the nested virtualization scenario described by the advisory, the host is itself a guest virtual machine.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-105733
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7807, 11 23H2 10.0.22631.7652, 11 24H2 10.0.26100.9711, 11 25H2 10.0.26200.9711, 11 26H1 10.0.28000.3231
Windows Server - addressed in versions 2022 10.0.20348.5761, 2025 10.0.26100.33650
Windows Server - addressed in versions 2022 10.0.20348.5761, 2025 10.0.26100.33650