Off-by-one in Microsoft Windows - CVE-2026-113771
Published: November 11, 2026
Vulnerability identifier: #VU164937
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-113771
CWE-ID: CWE-193
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate privileges locally.
The vulnerability exists due to an off-by-one error in the Windows Container Isolation FS Filter Driver (unionfs.sys) when processing locally initiated operations. A local user can trigger the error through local operations to escalate privileges.
Affected software
Microsoft Windows
How to mitigate CVE-2026-113771
Install security update from vendor's website.
Microsoft Windows - update to 11 26H1 10.0.28000.3501