CVE-2020-0638 Microsoft Update Notification Manager Privilege Escalation Vulnerability
Microsoft Update Notification Manager contains an unspecified vulnerability that allows for privilege escalation.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 23 May 2022.
- CISA lists it as known to be used in ransomware campaigns.
- Rated High severity (CVSS 7.8, scored by CISA).
- It has been in the catalogue for 1,628 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
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'.
Affected Versions
| Product | Versions |
|---|---|
| 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 |
| Microsoft Windows 10 Version 1903 for ARM64-based Systems | unspecified |
| Microsoft Windows 10 Version 1903 for 32-bit Systems | unspecified |
| Microsoft Windows 10 Version 1903 for x64-based Systems | unspecified |
| Microsoft Windows Server | 2019 2019 (Core installation) version 1803 (Core Installation) |
| Microsoft Windows Server, version 1903 (Server Core installation) | unspecified |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Microsoft Update Notification Manager. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
- 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
Vendor Advisories
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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