CVE-2020-1084 — Connected User Experiences and Telemetry Service Denial of Service Vulnerability

Executive Summary

A Denial Of Service vulnerability exists when Connected User Experiences and Telemetry Service fails to validate certain function values. An attacker who successfully exploited this vulnerability could deny dependent security feature functionality. To exploit this vulnerability, an attacker would have to log on to an affected system and run a specially crafted application. The security update addresses the vulnerability by correcting how the Connected User Experiences and Telemetry Service validates certain function values.

Overview

5.5

CVSS MEDIUM

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Denial of Service

Released May 12 2020

Last Updated May 12 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.01025 — 0.59051 percentile

NVD CVSS 5.5 MEDIUM — matches MSRC

CVSS Vector

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

ATTACK VECTOR

Local

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

Low

USER INTERACTION

None

SCOPE

Unchanged

CONFIDENTIALITY

None

INTEGRITY

None

AVAILABILITY

High

EXPLOIT CODE MATURITY

Proof-of-Concept

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 5.0

EPSS Score

0.01025

probability of exploitation in the next 30 days

0.59051 percentile - updated 2026-06-21

View on FIRST.org

Affected Products

26 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 10 for 32-bit Systems	`4556826 (Security Update)`	Important	Denial of Service	Yes
Windows 10 for x64-based Systems	`4556826 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1607 for 32-bit Systems	`4556813 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1607 for x64-based Systems	`4556813 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for 32-bit Systems	`4556812 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for ARM64-based Systems	`4556812 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for x64-based Systems	`4556812 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for 32-bit Systems	`4556807 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for ARM64-based Systems	`4556807 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for x64-based Systems	`4556807 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for 32-bit Systems	`4551853 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for ARM64-based Systems	`4551853 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for x64-based Systems	`4551853 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for 32-bit Systems	`4556799 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for ARM64-based Systems	`4556799 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for x64-based Systems	`4556799 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for 32-bit Systems	`4556799 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for ARM64-based Systems	`4556799 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for x64-based Systems	`4556799 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2016	`4556813 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2016 (Server Core installation)	`4556813 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019	`4551853 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019 (Server Core installation)	`4551853 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 1803 (Server Core Installation)	`4556807 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 1903 (Server Core installation)	`4556799 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 1909 (Server Core installation)	`4556799 (Security Update)`	Important	Denial of Service	Yes

Patches

6 patches

Article	Type	Restart
`4556826`	Security Update	Yes
`4556813`	Security Update	Yes
`4556812`	Security Update	Yes
`4556807`	Security Update	Yes
`4551853`	Security Update	Yes
`4556799`	Security Update	Yes

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

Somaro, Sai Cheng with ChengDu MeetSec Technology Co., Ltd., @edwardzpeng, Somaro2

References

MSRC Advisory MITRE NVD