Vulnerability · Published Aug 11, 2026 · Assigned by microsoft

CVE-2026-62775Windows Container Isolation FS Filter Driver (unionfs.sys) Information Disclosure Vulnerability

Medium 5.5

In plain English

A medium-severity incorrect authorization in Windows 11 version 26H1 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).

Severity (CVSS 3.1)5.5Medium
Exploit odds (30 days)0.4%top 71.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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

Affected products (as reported)

VendorProductVersions
Microsoft Windows 11 version 26H1 10.0.28000.0 – before 10.0.28000.2704

Weakness: CWE-863 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

References