CVE-2026-21533

Windows Remote Desktop Services Elevation of Privilege Vulnerability

CVSS 3.1 High 7.8Known exploited (CISA KEV)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

Description

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

Key data

CVSS 3.1 High 7.8

Score published by microsoft in the CVE record.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

Attack vector: Local
The attacker needs local access to the system, or to trick a user into running something.
Attack complexity: Low
No special conditions are needed. The attack can be repeated at will.
Privileges required: Low
A basic user account is needed.
User interaction: None
No action from any user is needed.
Scope: Unchanged
The impact stays within the vulnerable component.
Confidentiality impact: High
Serious or total effect on the secrecy of data.
Integrity impact: High
Serious or total effect on the trustworthiness of data.
Availability impact: High
Serious or total effect on availability.

Metric	Value	What it means
Attack vector	Local	The attacker needs local access to the system, or to trick a user into running something.
Attack complexity	Low	No special conditions are needed. The attack can be repeated at will.
Privileges required	Low	A basic user account is needed.
User interaction	None	No action from any user is needed.
Scope	Unchanged	The impact stays within the vulnerable component.
Confidentiality impact	High	Serious or total effect on the secrecy of data.
Integrity impact	High	Serious or total effect on the trustworthiness of data.
Availability impact	High	Serious or total effect on availability.

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at first.org/cvss.

EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score: 0.04335 (4.3% probability)
Percentile: 91.3%
Scores of: Nov 10, 2026
Model: v2026.06.15

CISA Known Exploited Vulnerabilities

This CVE is listed in the CISA KEV catalog.

Name in the catalog: Microsoft Windows Improper Privilege Management Vulnerability
Added to the catalog: Feb 10, 2026
Federal due date: Mar 3, 2026

CISA assessment as of Feb 11, 2026

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.

Exploitation: Recorded by CISA as active
Automatable: no
Technical impact: total

Weakness (CWE)

CWE catalog version 5.0.

CWE-269Improper Privilege Management

Affected products

Products listed in the CVE record, as the CNA published them.

Microsoft Windows 10 Version 1607
- affected: 10.0.14393.0 up to before 10.0.14393.8868
Microsoft Windows 10 Version 1809
- affected: 10.0.17763.0 up to before 10.0.17763.8389
Microsoft Windows 10 Version 21H2
- affected: 10.0.19044.0 up to before 10.0.19044.6937
Microsoft Windows 10 Version 22H2
- affected: 10.0.19045.0 up to before 10.0.19045.6937
Microsoft Windows 11 version 22H3
- affected: 10.0.22631.0 up to before 10.0.22631.6649
Microsoft Windows 11 Version 23H2
- affected: 10.0.22631.0 up to before 10.0.22631.6649
Microsoft Windows 11 Version 24H2
- affected: 10.0.26100.0 up to before 10.0.26100.7840
Microsoft Windows 11 Version 25H2
- affected: 10.0.26200.0 up to before 10.0.26200.7840
Microsoft Windows 11 version 26H1
- affected: 10.0.28000.0 up to before 10.0.28000.1575
Microsoft Windows 11 Version 26H1
- affected: 10.0.28000.0 up to before 10.0.28000.1575
Microsoft Windows Server 2012
- affected: 6.2.9200.0 up to before 6.2.9200.25923
Microsoft Windows Server 2012 (Server Core installation)
- affected: 6.2.9200.0 up to before 6.2.9200.25923
Microsoft Windows Server 2012 R2
- affected: 6.3.9600.0 up to before 6.3.9600.23022
Microsoft Windows Server 2012 R2 (Server Core installation)
- affected: 6.3.9600.0 up to before 6.3.9600.23022
Microsoft Windows Server 2016
- affected: 10.0.14393.0 up to before 10.0.14393.8868
Microsoft Windows Server 2016 (Server Core installation)
- affected: 10.0.14393.0 up to before 10.0.14393.8868
Microsoft Windows Server 2019
- affected: 10.0.17763.0 up to before 10.0.17763.8389
Microsoft Windows Server 2019 (Server Core installation)
- affected: 10.0.17763.0 up to before 10.0.17763.8389
Microsoft Windows Server 2022
- affected: 10.0.20348.0 up to before 10.0.20348.4773
Microsoft Windows Server 2022, 23H2 Edition (Server Core installation)
- affected: 10.0.25398.0 up to before 10.0.25398.2149
Microsoft Windows Server 2025
- affected: 10.0.26100.0 up to before 10.0.26100.32370
Microsoft Windows Server 2025 (Server Core installation)
- affected: 10.0.26100.0 up to before 10.0.26100.32370

References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

Windows Remote Desktop Services Elevation of Privilege Vulnerability (msrc.microsoft.com)vendor-advisorypatch
vicarius.io/vsociety/posts/cve-2026-21533-detection-script-…
vicarius.io/vsociety/posts/cve-2026-21533-mitigation-script…

Timeline

ID reservedDec 30, 2025
Added to CISA KEVFeb 10, 2026
Record publishedFeb 10, 2026
Record last updatedAug 19, 2026

Look up another CVE

About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.

Cloud VPS DDoS protection

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:52 UTC. Sources and licenses