Execution with unnecessary privileges in Microsoft Windows and Windows Server - CVE-2026-124226
Published: November 11, 2026
Vulnerability identifier: #VU165500
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-2026-124226
CWE-ID: CWE-250
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to bypass Windows Defender Application Control and PowerShell Constrained Language Mode restrictions, allowing untrusted code to run with capabilities those protections are designed to block.
The vulnerability exists due to execution with unnecessary privileges in Windows PowerShell workflow handling when attacker-controlled workflow-definition data is inserted into a generated wrapper that runs in Full Language Mode. A local user can define and invoke a crafted workflow while executing Windows PowerShell locally under Constrained Language Mode to bypass the enforced security restrictions.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-124226
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7846, 10 22H2 10.0.19045.7846, 10 1607 10.0.14393.9688, 10 1809 10.0.17763.9487, 11 23H2 10.0.22631.7711, 11 24H2 10.0.26100.9968, 11 25H2 10.0.26200.9968, 11 26H1 10.0.28000.3501
Windows Server - addressed in versions 2016 10.0.14393.9688, 2019 10.0.17763.9487, 2022 10.0.20348.5870, 2025 10.0.26100.33812
Windows Server - addressed in versions 2016 10.0.14393.9688, 2019 10.0.17763.9487, 2022 10.0.20348.5870, 2025 10.0.26100.33812