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MicrosoftCVE-2026-62775

Microsoft Windows 11 version 26H1: improper authorization

Medium5.5CVE-2026-62775 · Published Aug 11, 2026 · updated Aug 13, 2026

Incorrect authorization in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to disclose information locally.

Microsoft advisory

Affected versions

PackageAffectedFixed in
Windows 11 version 26H1
Product
>= 10.0.28000.0, < 10.0.28000.270410.0.28000.2704
Details and references
CVSS 3.1
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Severity from
the vendor (its own CVE record or advisory)
Weakness
CWE-863

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