---
id: "CVE-2026-21533"
kind: "vulnerability"
aliases: ["CVE-2026-21533"]
title: "Improper privilege management in Windows Remote Desktop allows an authorized attacker to elevate privileges locally"
severity: "high"
cvss: 7.8
epss: null
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Microsoft Windows", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "microsoft windows 10 1607", "fixed": ["10.0.14393.8868"], "affected": "< 10.0.14393.8868", "ecosystem": "vendor"}, {"name": "microsoft windows 10 1809", "fixed": ["10.0.17763.8389"], "affected": "< 10.0.17763.8389", "ecosystem": "vendor"}, {"name": "microsoft windows 10 21h2", "fixed": ["10.0.19044.6937"], "affected": "< 10.0.19044.6937", "ecosystem": "vendor"}, {"name": "microsoft windows 10 22h2", "fixed": ["10.0.19045.6937"], "affected": "< 10.0.19045.6937", "ecosystem": "vendor"}, {"name": "microsoft windows 11 23h2", "fixed": ["10.0.22631.6649"], "affected": "< 10.0.22631.6649", "ecosystem": "vendor"}, {"name": "microsoft windows 11 24h2", "fixed": ["10.0.26100.7781"], "affected": "< 10.0.26100.7781", "ecosystem": "vendor"}, {"name": "microsoft windows 11 25h2", "fixed": ["10.0.26200.7781"], "affected": "< 10.0.26200.7781", "ecosystem": "vendor"}, {"name": "microsoft windows server 2012", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "microsoft windows server 2012", "fixed": [], "affected": "= r2", "ecosystem": "vendor"}, {"name": "microsoft windows server 2016", "fixed": ["10.0.14393.8868"], "affected": "< 10.0.14393.8868", "ecosystem": "vendor"}, {"name": "microsoft windows server 2019", "fixed": ["10.0.17763.8389"], "affected": "< 10.0.17763.8389", "ecosystem": "vendor"}, {"name": "microsoft windows server 2022", "fixed": ["10.0.20348.4711"], "affected": "< 10.0.20348.4711", "ecosystem": "vendor"}, {"name": "microsoft windows server 2022 23h2", "fixed": ["10.0.25398.2149"], "affected": "< 10.0.25398.2149", "ecosystem": "vendor"}, {"name": "microsoft windows server 2025", "fixed": ["10.0.26100.32313"], "affected": "< 10.0.26100.32313", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "infrastructure", "remote-desktop-services", "windows"]
not_affected_if: ["no-rds-hosts"]
published_at: "2026-02-10T00:00:00+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-21533", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-21533", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# Improper privilege management in Windows Remote Desktop allows an authorized attacker to elevate privileges locally

Windows Remote Desktop Services has an improper privilege management flaw that lets an authorized user raise their privileges on the machine. CISA lists it as actively exploited in the wild.

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

## Affected

- vendor:Microsoft Windows affected ? fixed ?
- vendor:microsoft windows 10 1607 affected < 10.0.14393.8868 fixed 10.0.14393.8868
- vendor:microsoft windows 10 1809 affected < 10.0.17763.8389 fixed 10.0.17763.8389
- vendor:microsoft windows 10 21h2 affected < 10.0.19044.6937 fixed 10.0.19044.6937
- vendor:microsoft windows 10 22h2 affected < 10.0.19045.6937 fixed 10.0.19045.6937
- vendor:microsoft windows 11 23h2 affected < 10.0.22631.6649 fixed 10.0.22631.6649
- vendor:microsoft windows 11 24h2 affected < 10.0.26100.7781 fixed 10.0.26100.7781
- vendor:microsoft windows 11 25h2 affected < 10.0.26200.7781 fixed 10.0.26200.7781
- vendor:microsoft windows server 2012 affected ? fixed ?
- vendor:microsoft windows server 2012 affected = r2 fixed ?
- vendor:microsoft windows server 2016 affected < 10.0.14393.8868 fixed 10.0.14393.8868
- vendor:microsoft windows server 2019 affected < 10.0.17763.8389 fixed 10.0.17763.8389
- vendor:microsoft windows server 2022 affected < 10.0.20348.4711 fixed 10.0.20348.4711
- vendor:microsoft windows server 2022 23h2 affected < 10.0.25398.2149 fixed 10.0.25398.2149
- vendor:microsoft windows server 2025 affected < 10.0.26100.32313 fixed 10.0.26100.32313

## Fix

Apply the Microsoft security update for CVE-2026-21533 per vendor instructions; the sources do not name the patched build.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2026-21533
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-21533

## From the sources

Microsoft Windows Remote Desktop Services contains an improper privilege management vulnerability that could allow an authorized attacker to elevate privileges locally.

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_