---
id: "CVE-2026-112799"
page: "https://infrastack.ai/live/CVE-2026-112799"
kind: "vulnerability"
aliases: ["CVE-2026-112799"]
title: "Windows Projected File System: stack overflow lets a local user gain admin rights"
severity: "high"
cvss: 7.8
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "Windows 10 1809", "fixed": ["10.0.17763.9487"], "affected": ">= 10.0.17763.0, < 10.0.17763.9487", "ecosystem": "microsoft"}, {"name": "Windows 10 21H2", "fixed": ["10.0.19044.7846"], "affected": ">= 10.0.19044.0, < 10.0.19044.7846", "ecosystem": "microsoft"}, {"name": "Windows 10 22H2", "fixed": ["10.0.19045.7846"], "affected": ">= 10.0.19045.0, < 10.0.19045.7846", "ecosystem": "microsoft"}, {"name": "Windows 11 23H2", "fixed": ["10.0.22631.7711"], "affected": ">= 10.0.22631.0, < 10.0.22631.7711", "ecosystem": "microsoft"}, {"name": "Windows 11 24H2", "fixed": ["10.0.26100.9974"], "affected": ">= 10.0.26100.0, < 10.0.26100.9974", "ecosystem": "microsoft"}]
ecosystems: []
tags: ["infrastructure", "local", "privilege-escalation", "projected-file-system", "windows"]
not_affected_if: ["feature-disabled", "no-local-accounts"]
published_at: "2026-11-10T19:18:42+00:00"
first_seen_at: "2026-11-10T19:24:33+00:00"
updated_at: "2026-11-11T00:06:19+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-112799", "first_seen_at": "2026-11-10T19:24:33+00:00"}, {"source": "analyst", "url": "https://radar.offseq.com/threat/cve-2026-112799-cwe-121-stack-based-buffer-overflow-in-microsoft-windows-10-version-1809-93b8cc423e6437e1", "first_seen_at": "2026-11-11T00:06:19+00:00", "cites": ["https://radar.offseq.com/threat/cve-2026-112799-cwe-121-stack-based-buffer-overflow-in-microsoft-windows-10-version-1809-93b8cc423e6437e1"]}]
exploit_sources: []
---

# Windows Projected File System: stack overflow lets a local user gain admin rights

Link for people: https://infrastack.ai/live/CVE-2026-112799 (this .md is for agents)

A stack-based buffer overflow in the Windows Projected File System lets a user with a local account gain higher privileges (CVSS 7.8). Microsoft shipped fixes in the November 2026 updates; no exploitation or public exploit is reported.

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

## Affected

- microsoft:Windows 10 1809 affected >= 10.0.17763.0, < 10.0.17763.9487 fixed 10.0.17763.9487
- microsoft:Windows 10 21H2 affected >= 10.0.19044.0, < 10.0.19044.7846 fixed 10.0.19044.7846
- microsoft:Windows 10 22H2 affected >= 10.0.19045.0, < 10.0.19045.7846 fixed 10.0.19045.7846
- microsoft:Windows 11 23H2 affected >= 10.0.22631.0, < 10.0.22631.7711 fixed 10.0.22631.7711
- microsoft:Windows 11 24H2 affected >= 10.0.26100.0, < 10.0.26100.9974 fixed 10.0.26100.9974

## How to check

Run winver (or [System.Environment]::OSVersion) and compare the full build number (e.g. 10.0.19045.xxxx) to the fixed builds in the fix field; a lower build is exposed. ProjFS is an optional feature: Get-WindowsOptionalFeature -Online -FeatureName Client-ProjFS. Also check that your machine has local users or untrusted code that could run on it.

## Fix

Install the November 2026 (Patch Tuesday) cumulative update for your Windows version. Fixed builds reported: Win10 1809 10.0.17763.9487, Win10 21H2 10.0.19044.7846, Win10 22H2 10.0.19045.7846, Win11 23H2 10.0.22631.7711, Win11 24H2 10.0.26100.9974. Exact KB per version: see the Microsoft Security Update Guide entry (not read).

## Timeline

- 2026-11-10T19:24:33+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-112799
- 2026-11-11T00:06:19+00:00 analyst https://radar.offseq.com/threat/cve-2026-112799-cwe-121-stack-based-buffer-overflow-in-microsoft-windows-10-version-1809-93b8cc423e6437e1 — MSRC page not readable via web-cli; builds/fixed versions from OffSeq mirror of the CVE record (6 of ~10 products seen) and VulniPulse (Server 2019/2022/2025 named). Nothing verified; KB numbers not found. Not exploited per sources.

## Documents

- [describes] OffSeq: CVE-2026-112799 affected builds (rewrite of CVE record) https://radar.offseq.com/threat/cve-2026-112799-cwe-121-stack-based-buffer-overflow-in-microsoft-windows-10-version-1809-93b8cc423e6437e1

## From the sources

Stack-based buffer overflow in Windows Projected File System allows an authorized attacker to elevate privileges locally.

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_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_