Auth bypass in Microsoft Windows 11 Version 26h1
CVE-2026-62775
Incorrect authorization in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to disclose information locally.
Vulnerability class: Broken Access Control
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Microsoft Windows 11 Version 26h1 — versions 10.0.28000.0
Weakness classification (CWE)
References
- Windows Container Isolation FS Filter Driver (unionfs.sys) Information Disclosure Vulnerability (vendor-advisory, patch)
Frequently asked questions
- What is CVE-2026-62775?
- CVE-2026-62775 is a medium-severity vulnerability in Microsoft Windows 11 Version 26h1, classified under Incorrect Authorization. CVSS score: 5.5/10. Published 2026-08-11.
- How severe is CVE-2026-62775?
- Medium severity. CVSS v3 base score is 5.5 out of 10.