CVE-2026-62772: Windows Container Isolation FS Filter Driver (unionfs.sys) Elevation of Privilege Vulnerability
Published Aug 11, 2026
·Updated
Heap-based buffer overflow 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
2 affected componentsFixes available
Microsoft Windows 11=26H1
10.0.28000.2704
Microsoft Windows 11=26H1
10.0.28000.2704
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 10.0.28000.2704Patch KB5121000
Event History
Aug 11, 2026
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
CVE Published
via MITRE·05:04 PM
Data Sourced
via MITRE·05:04 PM
DescriptionSeverity
Data Sourced
via NVD·05:18 PM
DescriptionSeverityWeakness
Frequently Asked Questions
1
What is the severity of CVE-2026-62772?
The severity of CVE-2026-62772 is high, with a CVSS score of 7.8.
2
How do I fix CVE-2026-62772?
To fix CVE-2026-62772, apply the latest security updates provided by Microsoft for Windows 11.
3
What type of vulnerability is CVE-2026-62772?
CVE-2026-62772 is a heap-based buffer overflow vulnerability.
4
What can an attacker achieve with CVE-2026-62772?
An attacker can elevate privileges locally on a system by exploiting CVE-2026-62772.
5
Which software is affected by CVE-2026-62772?
CVE-2026-62772 affects Microsoft Windows 11.