CVE-2026-97792: Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability
Improper access control in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.
Other sources
Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.33650Patch KB5126646 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26200.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26300.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7652Patch KB5126653 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5761Patch KB5126655
Event History
Frequently Asked Questions
Who is exposed to this vulnerability?
Systems running the Microsoft Windows products listed as affected, including Windows 11, Windows Server 2022, Windows Server 2025, and the Windows Container Isolation FS Filter Driver, may be exposed.
What does an attacker need to exploit it?
An attacker needs local access and must already be authorized on the affected system with low privileges. No user interaction is required.
What is the likely impact of successful exploitation?
Successful exploitation allows local elevation of privilege. The provided severity vector indicates high impacts to confidentiality, integrity, and availability.