Important CVSS 7.8 EPSS 0.00939 2020-09 archive

Executive Summary

An elevation of privilege vulnerability exists when the Windows InstallService improperly handles memory. To exploit this vulnerability, an attacker would first have to gain execution on the victim system. An attacker could then run a specially crafted application to elevate privileges. The security update addresses the vulnerability by correcting how the Windows InstallService handles memory.

Overview

7.8
CVSS HIGH
Important
MS Severity
Not Exploited
MS Exploit Status
Less Likely
MS Exploit Likelihood
Category Elevation of Privilege
Released Sep 8 2020
Last Updated Sep 8 2020
Publicly Disclosed No
CISA KEV Not Listed
Known Exploits None Known
EPSS Score 0.00939 — 0.56225 percentile
NVD CVSS 7.8 HIGH — matches 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
High
INTEGRITY
High
AVAILABILITY
High
EXPLOIT CODE MATURITY
Proof-of-Concept
REMEDIATION LEVEL
Official Fix
REPORT CONFIDENCE
Confirmed
Temporal Score: 7.0

EPSS Score

0.00939
probability of exploitation in the next 30 days
0.56225 percentile - updated 2026-06-21
View on FIRST.org

Affected Products

12 affected products
Product KB Article Severity Impact Restart Required
Windows 10 Version 1903 for 32-bit Systems 4574727 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 1903 for ARM64-based Systems 4574727 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 1903 for x64-based Systems 4574727 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 1909 for 32-bit Systems 4574727 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 1909 for ARM64-based Systems 4574727 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 1909 for x64-based Systems 4574727 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 2004 for 32-bit Systems 4571756 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 2004 for ARM64-based Systems 4571756 (Security Update) Important Elevation of Privilege Yes
Windows 10 Version 2004 for x64-based Systems 4571756 (Security Update) Important Elevation of Privilege Yes
Windows Server, version 1903 (Server Core installation) 4574727 (Security Update) Important Elevation of Privilege Yes
Windows Server, version 1909 (Server Core installation) 4574727 (Security Update) Important Elevation of Privilege Yes
Windows Server, version 2004 (Server Core installation) 4571756 (Security Update) Important Elevation of Privilege Yes

Patches

2 patches
Article Type Restart
4574727 Security Update Yes
4571756 Security Update Yes

Known Exploits

Acknowledgments

anonymous