Unintended Proxy or Intermediary in Microsoft Windows and Windows Server - CVE-2026-88235
Published: November 11, 2026
Vulnerability identifier: #VU165572
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-2026-88235
CWE-ID: CWE-441
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate privileges locally and create files in protected system locations with TrustedInstaller authority.
The vulnerability exists due to an unintended proxy or intermediary ('confused deputy') weakness in Servicing Stack Updates when handling local servicing operations. A local user can abuse the component's privileged authority to create files in protected system locations with TrustedInstaller authority.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-88235
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 10.0.14393.9681, 10 1809 10.0.17763.9487, 11 23H2 10.0.22631.7711
Windows Server - addressed in versions 2016 10.0.14393.9681, 2019 10.0.17763.9487, 2022 10.0.20348.5870
Windows Server - addressed in versions 2016 10.0.14393.9681, 2019 10.0.17763.9487, 2022 10.0.20348.5870