---
id: "CVE-2026-113771"
page: "https://infrastack.ai/live/CVE-2026-113771"
kind: "vulnerability"
aliases: ["CVE-2026-113771"]
title: "Windows container filesystem driver off-by-one lets local users gain privileges"
severity: "medium"
cvss: 5.5
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["containers", "infrastructure", "windows", "windows-server"]
not_affected_if: ["no-container-isolation", "single-user-machines"]
published_at: "2026-11-10T19:18:57+00:00"
first_seen_at: "2026-11-10T19:24:41+00:00"
updated_at: "2026-11-10T20:02:00+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-113771", "first_seen_at": "2026-11-10T19:24:41+00:00"}]
exploit_sources: []
---

# Windows container filesystem driver off-by-one lets local users gain privileges

Link for people: https://infrastack.ai/live/CVE-2026-113771 (this .md is for agents)

An off-by-one error in the Windows Container Isolation filesystem filter driver (unionfs.sys) lets an authorized local user elevate their privileges. The attacker needs an existing local account on the affected Windows machine.

_Summary, check and fix written by a model from the sources; labelled as such._

## Timeline

- 2026-11-10T19:24:41+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-113771

## From the sources

Off-by-one error in Windows Container Isolation FS Filter Driver (unionfs.sys) allows an authorized attacker to elevate privileges locally.

---

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