I just joined the thread and was looking at previous posts. The -18, 19 and 20 are system services and normal.
Code:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\S-1-5-21-2452422238-2317045706-931954555-1000
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList\S-1-5-21-2452422238-2317045706-931954555-501
These two SIDs are disturbing. The S-1-5-21-xxx-501 is a Guest Account that doesn't need a password. By default, Windows disables Guest Accounts.
I'm not sure what the SID S-1-5-21-xxx-1000 might be but it's assigned to the same domain (class). It could have Administrative rights to control a network group.
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