CVE REMEDIATION GUIDE
CISA KEV · Known exploitedHighResearch in progress

CVE-2020-0638 remediation guide

Microsoft Update Notification Manager

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'.

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Research in progress

A verified fixed-version field is not available. Use the linked NVD and supporting references, then confirm the vendor-supported path before changing production systems.

ProductMicrosoft Update Notification Manager
Affected versions10 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, unspecified, 2019, 2019 (Core installation), version 1803 (Core Installation)
Fixed versionsNo verified fixed-version field is available yet
Priority basisImmediate · CVSS 7.8 · EPSS 3.04%
01

Identify the affected asset

Confirm whether Microsoft Update Notification Manager is installed, record the deployed version and installation path, and identify exposed interfaces.

  • Record the product name, package or appliance identifier, and installed version.
  • Identify internet-facing, administrative, API, and internal access paths.
  • Preserve the pre-change configuration and relevant service logs.
02

Validate the affected-version match

Compare the deployed version with the affected range: 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, unspecified, 2019, 2019 (Core installation), version 1803 (Core Installation). Treat incomplete inventory results as unresolved.

03

Prioritize with independent signals

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog. Combine this signal with asset criticality, exposure, compensating controls, and business impact.

04

Apply supported remediation

Apply updates per vendor instructions.

05

Verify the result

Confirm the resulting version, service health, authentication and access paths, monitoring coverage, and relevant security logs.

  • Confirm the expected version and package state.
  • Run a functional health check for critical service paths.
  • Review authentication, error, application, and security monitoring logs.
  • Reassess exposure if the supported fix cannot be applied.

Operational boundary

This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.