CVE-2020-1466 — Windows Remote Desktop Gateway (RD Gateway) Denial of Service Vulnerability

Executive Summary

A denial of service vulnerability exists in Windows Remote Desktop Gateway (RD Gateway) 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 RD Gateway 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 RD Gateway services. The update addresses the vulnerability by correcting how RD Gateway handles connection requests.

Overview

7.8

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

N/A

MS Exploit Likelihood

Category Denial of Service

Released Aug 11 2020

Last Updated Aug 11 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.03829 — 0.88717 percentile

NVD CVSS 7.8 HIGH — differs from MSRC

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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: 6.7

EPSS Score

0.03829

probability of exploitation in the next 30 days

0.88717 percentile - updated 2026-06-21

View on FIRST.org

Affected Products

4 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows Server 2012 4571736 (Monthly Rollup) 4571702 (Security Only) Important Denial of Service 4565537 Base: 7.5 Temporal: 6.7 Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C Yes 4571736 4571702 Windows Server 2012 (Server Core installation) 4571736 (Monthly Rollup) 4571702 (Security Only) Important Denial of Service 4565537 Base: 7.5 Temporal: 6.7 Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C Yes 4571736 4571702 Windows Server 2012 R2 4571703 (Monthly Rollup) 4571723 (Security Only) Important Denial of Service 4565541 Base: 7.5 Temporal: 6.7 Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C Yes 4571703 4571723 Windows Server 2012 R2 (Server Core installation) 4571703 (Monthly Rollup) 4571723 (Security Only) Important Denial of Service 4565541 Base: 7.5 Temporal: 6.7 Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C Yes 4571703 4571723 Windows Server 2016	`4571694 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2016 (Server Core installation)	`4571694 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019	`4565349 (Security Update)`	Important	Denial of Service	Yes
Windows Server 2019 (Server Core installation)	`4565349 (Security Update)`	Important	Denial of Service	Yes

Patches

2 patches

Article	Type	Restart
`4571694`	Security Update	Yes
`4565349`	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

Microsoft Platform Security Assurance & Vulnerability Research

References

MSRC Advisory MITRE NVD