---
id: CVE-2026-97790
title: >-
  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.
summary: >-
  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.
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N'
cwe:
  - CWE-59
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T20:19:40.800'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-97790'
references:
  - url: 'https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-97790'
    label: secure@microsoft.com
tags:
  - nvd
ingestedAt: '2026-10-13T19:43:29.306Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.