Description
Improper link resolution before file access ('link following') in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to perform tampering locally.
Affected products
microsoft: windows 11 24h2; microsoft: windows 11 25h2; microsoft: windows 11 26h1; microsoft: windows 11 26h2; microsoft: windows server 2022; microsoft: windows server 2025
References1
- msrc.microsoft.com/update-guide/vulnerability/CVE-2026-97790 PatchVendor Advisory
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 0% percentile: 33 · as of 11 November 2026
- CWE
- CWE-59
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