CVE-2020-0637 — Remote Desktop Web Access Information Disclosure Vulnerability

Executive Summary

An information disclosure vulnerability exists when Remote Desktop Web Access improperly handles credential information. An attacker who successfully exploited this vulnerability could obtain legitimate users' credentials. To exploit this vulnerability, an attacker would need access to a vulnerable server with the Remote Desktop Web Access role. The security update addresses the vulnerability by correcting how Remote Desktop Web Access handles credential information.

Overview

6.5

CVSS MEDIUM

Important

MS Severity

Not Exploited

MS Exploit Status

N/A

MS Exploit Likelihood

Category Information Disclosure

Released Jan 14 2020

Last Updated Jan 14 2020

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.05027 — 0.91365 percentile

NVD CVSS 6.5 MEDIUM — differs from MSRC

CVSS Vector

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

ATTACK VECTOR

Network

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

Low

USER INTERACTION

None

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

None

AVAILABILITY

None

EXPLOIT CODE MATURITY

Proof-of-Concept

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 5.1

EPSS Score

0.05027

probability of exploitation in the next 30 days

0.91365 percentile - updated 2026-07-25

View on FIRST.org

Affected Products

4 affected products

Product	KB Article	Severity	Impact	Restart Required
Windows Server 2008 R2 for x64-based Systems Service Pack 1 4534310 (Monthly Rollup) 4534314 (Security Only) Important Information Disclosure 4530734 Base: 5.7 Temporal: 5.1 Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C Yes 4534310 Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation) 4534310 (Monthly Rollup) 4534314 (Security Only) Important Information Disclosure 4530734 Base: 5.7 Temporal: 5.1 Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C Yes 4534310 Windows Server 2012 4534283 (Monthly Rollup) 4534288 (Security Only) Important Information Disclosure 4530691 Base: 5.7 Temporal: 5.1 Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C Yes 4534283 4534288 Windows Server 2012 (Server Core installation) 4534283 (Monthly Rollup) 4534288 (Security Only) Important Information Disclosure 4530691 Base: 5.7 Temporal: 5.1 Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C Yes 4534283 4534288 Windows Server 2012 R2 4534297 (Monthly Rollup) 4534309 (Security Only) Important Information Disclosure 4530702 Base: 5.7 Temporal: 5.1 Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C Yes 4534297 4534309 Windows Server 2012 R2 (Server Core installation) 4534297 (Monthly Rollup) 4534309 (Security Only) Important Information Disclosure 4530702 Base: 5.7 Temporal: 5.1 Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C Yes 4534297 4534309 Windows Server 2016	`4534271 (Security Update)`	Important	Information Disclosure	Yes
Windows Server 2016 (Server Core installation)	`4534271 (Security Update)`	Important	Information Disclosure	Yes
Windows Server 2019	`4534273 (Security Update)`	Important	Information Disclosure	Yes
Windows Server 2019 (Server Core installation)	`4534273 (Security Update)`	Important	Information Disclosure	Yes

Patches

2 patches

Article	Type	Restart
`4534271`	Security Update	Yes
`4534273`	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

Bence Bálint

References

MSRC Advisory MITRE NVD