---
id: "CVE-2026-88245"
page: "https://infrastack.ai/live/CVE-2026-88245"
kind: "vulnerability"
aliases: ["CVE-2026-88245"]
title: "Windows Brokering File System: missing authentication lets local users gain privileges"
severity: "high"
cvss: 7.8
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: [{"name": "Windows Brokering File System", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "Windows Server 2025", "fixed": ["10.0.26100.33822"], "affected": ">= 10.0.26100.0, < 10.0.26100.33822", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["infrastructure", "windows", "windows-server"]
not_affected_if: ["no-local-users"]
published_at: "2026-11-10T19:21:34+00:00"
first_seen_at: "2026-11-10T19:25:20+00:00"
updated_at: "2026-11-10T20:39:11+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-88245", "first_seen_at": "2026-11-10T19:25:20+00:00"}, {"source": "analyst", "url": "https://radar.offseq.com/threat/cve-2026-88245-cwe-306-missing-authentication-for-critical-functionality-in-microsoft-windows-server-dec22066d5d283b0", "first_seen_at": "2026-11-10T20:39:11+00:00", "cites": ["https://radar.offseq.com/threat/cve-2026-88245-cwe-306-missing-authentication-for-critical-functionality-in-microsoft-windows-server-dec22066d5d283b0"]}]
exploit_sources: []
---

# Windows Brokering File System: missing authentication lets local users gain privileges

Link for people: https://infrastack.ai/live/CVE-2026-88245 (this .md is for agents)

The Windows Brokering File System has a critical function that lacks an authentication check. An attacker with a local account can use it to elevate their privileges on the machine.

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

## Affected

- vendor:Windows Brokering File System affected range not listed fixed no fixed version listed
- vendor:Windows Server 2025 affected >= 10.0.26100.0, < 10.0.26100.33822 fixed 10.0.26100.33822

## How to check

Run 'winver' or PowerShell '[System.Environment]::OSVersion.Version' on each Windows Server 2025 host (including Server Core); builds >= 10.0.26100.0 and < 10.0.26100.33822 are listed as affected. Also check Windows 11 24H2/25H2 hosts against the MSRC advisory, which was not readable here.

## Fix

Windows Server 2025: update to build 10.0.26100.33822 or later (per a CVE-record mirror; KB number not confirmed on MSRC).

## Timeline

- 2026-11-10T19:25:20+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-88245
- 2026-11-10T20:39:11+00:00 analyst https://radar.offseq.com/threat/cve-2026-88245-cwe-306-missing-authentication-for-critical-functionality-in-microsoft-windows-server-dec22066d5d283b0 — MSRC page unreadable by web-cli; affected/fixed range taken from OffSeq mirror of Microsoft CNA record (Server 2025 only listed). Nothing verified. Windows 11 builds and KB number not found; check MSRC.

## Documents

- [describes] OffSeq Threat Radar: CVE-2026-88245 (mirror of CNA record) https://radar.offseq.com/threat/cve-2026-88245-cwe-306-missing-authentication-for-critical-functionality-in-microsoft-windows-server-dec22066d5d283b0

## From the sources

Missing authentication for critical function in Windows Brokering File System allows an authorized attacker to elevate privileges locally.

---

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