CVE-2020-16927 — Windows Remote Desktop Protocol (RDP) Denial of Service Vulnerability

Executive Summary

A denial of service vulnerability exists in Remote Desktop Protocol (RDP) when an attacker connects to the target system using RDP and sends specially crafted requests. An attacker who successfully exploited this vulnerability could cause the RDP service on the target system to stop responding. To exploit this vulnerability, an attacker would need to run a specially crafted application against a server which provides Remote Desktop Protocol (RDP) services. The update addresses the vulnerability by correcting how RDP handles connection requests.

Overview

7.5

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Denial of Service

Released Oct 13 2020

Last Updated Oct 13 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.05486 — 0.91751 percentile

CVSS Vector

ATTACK VECTOR

Network

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

None

USER INTERACTION

None

SCOPE

Unchanged

Temporal Score: 6.7

EPSS Score

0.05486

probability of exploitation in the next 30 days

0.91751 percentile - updated 2026-06-20

View on FIRST.org

Affected Products

34 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows 10 for 32-bit Systems	`4580327 (Security Update)`	Important	Denial of Service	Yes
Windows 10 for x64-based Systems	`4580327 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1607 for 32-bit Systems	`4580346 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1607 for x64-based Systems	`4580346 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for 32-bit Systems	`4580328 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for ARM64-based Systems	`4580328 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1709 for x64-based Systems	`4580328 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for 32-bit Systems	`4580330 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for ARM64-based Systems	`4580330 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1803 for x64-based Systems	`4580330 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for 32-bit Systems	`4577668 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for ARM64-based Systems	`4577668 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1809 for x64-based Systems	`4577668 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for 32-bit Systems	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for ARM64-based Systems	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1903 for x64-based Systems	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for 32-bit Systems	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for ARM64-based Systems	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 1909 for x64-based Systems	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 2004 for 32-bit Systems	`4579311 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 2004 for ARM64-based Systems	`4579311 (Security Update)`	Important	Denial of Service	Yes
Windows 10 Version 2004 for x64-based Systems	`4579311 (Security Update)`	Important	Denial of Service	Yes
Windows 8.1 for 32-bit systems	`4580347 (Monthly Rollup) 4580358 (Security Only)`	Important	Denial of Service	Yes
Windows 8.1 for x64-based systems	`4580347 (Monthly Rollup) 4580358 (Security Only)`	Important	Denial of Service	Yes
Windows RT 8.1	`4580347 (Monthly Rollup)`	Important	Denial of Service	Yes
Windows Server 2012 R2	`4580347 (Monthly Rollup) 4580358 (Security Only)`	Important	Denial of Service	Yes
Windows Server 2012 R2 (Server Core installation)	`4580347 (Monthly Rollup) 4580358 (Security Only)`	Important	Denial of Service	Yes
Windows Server 2016	`4580346 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2016 (Server Core installation)	`4580346 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019	`4577668 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019 (Server Core installation)	`4577668 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 1903 (Server Core installation)	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 1909 (Server Core installation)	`4577671 (Security Update)`	Important	Denial of Service	Yes
Windows Server, version 2004 (Server Core installation)	`4579311 (Security Update)`	Important	Denial of Service	Yes

Patches

9 patches

Article	Type	Restart
`4580327`	Security Update	Yes
`4580346`	Security Update	Yes
`4580328`	Security Update	Yes
`4580330`	Security Update	Yes
`4577668`	Security Update	Yes
`4577671`	Security Update	Yes
`4579311`	Security Update	Yes
`4580347 (Monthly Rollup) 4580358`	Monthly Rollup	Yes
`4580347`	Monthly Rollup	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

VictorV (Tang Tianwen)

References

MSRC Advisory MITRE NVD