Is KB5000871 installed?

KB5000871.yaml

name: Custom.Windows.System.KB5000871
author: Matt Green - @mgreen27
description: |
   This artifact will check for KB5000871 in system Uninstall keys.
   
   KB5000871 is not visible via Get-Hotfix or Systeminfo so we need to query the 
   uninstall keys. Modify NameRegex to search for other installed applications.

reference:
    - https://support.microsoft.com/en-us/topic/description-of-the-security-update-for-microsoft-exchange-server-2019-2016-and-2013-march-2-2021-kb5000871-9800a6bb-0a21-4ee7-b9da-fa85b3e1d23b
    
type: CLIENT

parameters:
   - name: RegGlob		
     default: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\**
   - name: NameRegex		
     default: KB5000871

sources:
  - query: |
      LET uninstall = SELECT 
            timestamp(epoch=Key.Mtime.Sec) AS MTime,
            Key.Name as Name,
            DisplayName,
            DisplayVersion,
            InstallLocation,
            InstallSource,
            Language,
            Publisher,
            UninstallString,
            InstallDate
        FROM read_reg_key(globs=RegGlob)
        WHERE DisplayName =~ NameRegex
        
        SELECT 
            if(condition=uninstall,
                then= MTime) as PatchTime,
            if(condition= uninstall,
                then= DisplayName,
                else= NameRegex + ' not found.') as DisplayName
        FROM if(condition=uninstall,
            then= uninstall,
            else= scope())