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CVE-2026-32181 Microsoft CVE debrief

A local denial-of-service vulnerability in Microsoft Windows, stemming from improper privilege management in the Connected User Experiences and Telemetry service. An attacker with local, low-privileged access can exploit this flaw to cause service disruption without user interaction. The vulnerability affects multiple Windows 10, Windows 11, and Windows Server versions, with patches available that upgrade system builds to non-vulnerable versions. The CVSS 3.1 score of 5.5 reflects medium severity with high availability impact but no confidentiality or integrity impact.

Vendor
Microsoft
Product
Windows 10 Version 21H2
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-14
Original CVE updated
2026-05-26
Advisory published
2026-04-14
Advisory updated
2026-05-26

Who should care

Windows system administrators managing endpoints and servers; security operations teams monitoring for local privilege abuse; patch management teams prioritizing Microsoft security updates; organizations with strict availability requirements for Windows-based services.

Technical summary

The vulnerability exists in the Connected User Experiences and Telemetry service (DiagTrack) on Windows systems. Improper privilege management allows a locally authenticated attacker with low privileges to trigger a denial-of-service condition without requiring user interaction. The attack does not cross security boundaries (scope unchanged) and does not result in confidentiality or integrity compromise. Affected platforms span consumer Windows 10 and 11 releases across multiple feature updates, plus Windows Server 2022 and 2025 editions. Microsoft has released security updates that increment build numbers to remediate the flaw. The vulnerability was disclosed on 2026-04-14 and the NVD record was last modified on 2026-05-26.

Defensive priority

medium

Recommended defensive actions

  • Apply Microsoft security updates to bring affected systems to patched build versions: Windows 10 21H2 to 10.0.19044.7184 or later; Windows 10 22H2 to 10.0.19045.7184 or later; Windows 11 23H2 to 10.0.22631.6936 or later;
  • Windows 11 24H2 to 10.0.26100.8246 or later; Windows 11 25H2 to 10.0.26200.8246 or later; Windows 11 26H1 to 10.0.28000.1836 or later; Windows Server 2022 to 10.0.20348.5020 or later; Windows Server 2022 23H2 to 10.0.253
  • 98.2274 or later; and Windows Server 2025 to 10.0.26100.32690 or later.
  • Review and restrict local user privileges where possible to reduce attack surface for privilege management vulnerabilities.
  • Monitor for anomalous activity in the Connected User Experiences and Telemetry service (DiagTrack) as potential indicators of exploitation attempts.
  • Validate patch deployment through build version verification on all affected Windows endpoints and servers.

Evidence notes

CVE description confirms local attack vector with authorized attacker and denial-of-service outcome. CPE data from NVD specifies vulnerable Windows versions with exact build numbers for patched states. CVSS vector AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H corroborates local exploitation, low privileges required, no user interaction, and high availability impact. CWE-269 (Improper Privilege Management) identified by Microsoft. No KEV listing present.

Official resources

2026-04-14