How severe is CVE-2020-0638?

CVE-2020-0638 has a CVSS 3.1 base score of 7.8 (HIGH). EPSS estimates a 2.4% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2020-0638: Microsoft Update Notification Manager Privilege

CISA Known Exploited Vulnerabilities

Microsoft Update Notification Manager Privilege Escalation Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2022-05-23

Remediation due

2022-06-13

Ransomware

Known use

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2020-0638

Description

An elevation of privilege vulnerability exists in the way the Update Notification Manager handles files.To exploit this vulnerability, an attacker would first have to gain execution on the victim system, aka 'Update Notification Manager Elevation of Privilege Vulnerability'.

Severity

CVSS 3.1 · CISA7.8 HIGH

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

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impacttotal

Exploitation Context

as of October 17, 2026

All KEV statistics→

CISA added CVE-2020-0638 to the KEV catalog 860 days after its CVE record was published.
It is one of 391 Microsoft entries in the CISA KEV catalog, and one of 166 added in 2022.
Its current EPSS score (2.4%) is higher than that of 10% of CISA KEV entries.

Affected Products

Vendor	Product	Affected versions
Microsoft	Microsoft Windows	10 Version 1709 for 32-bit Systems 10 Version 1803 for 32-bit Systems 10 Version 1809 for ARM64-based Systems 10 Version 1803 for x64-based Systems 10 Version 1709 for ARM64-based Systems 10 Version 1709 for x64-based Systems 10 Version 1803 for ARM64-based Systems 10 Version 1809 for 32-bit Systems 10 Version 1809 for x64-based Systems
Microsoft	Microsoft Windows 10 Version 1903 for ARM64-based Systems	unspecified
Microsoft	Microsoft Windows 10 Version 1903 for 32-bit Systems	unspecified
Microsoft	Microsoft Windows 10 Version 1903 for x64-based Systems	unspecified
Microsoft	Microsoft Windows Server	2019 2019 (Core installation) version 1803 (Core Installation)
Microsoft	Microsoft Windows Server, version 1903 (Server Core installation)	unspecified
Microsoft	Microsoft Windows 10 Version 1909 for 32-bit Systems	unspecified
Microsoft	Microsoft Windows 10 Version 1909 for x64-based Systems	unspecified
Microsoft	Microsoft Windows Server, version 1909 (Server Core installation)	unspecified
Microsoft	Microsoft Windows 10 Version 1909 for ARM64-based Systems	unspecified

References

1 Links

Other references

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0638

Record Details

Published

2020-01-14

Last updated

2026-08-12

Assigner (CNA)

microsoft

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.