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Showing posts from April, 2020

Successful 4624 Anonymous Logons to Windows Server from External IPs?

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If you see successful 4624 event logs that look a little something like this in your Event Viewer showing an ANONYMOUS LOGON, an external IP (usually from Russia, Asia, USA, Ukraine) with an authentication package of NTLM, NTLMSSP, don't be alarmed - this is not an indication of a successful logon+access of your system even though it's logged as a 4624.


If your server has RDP or SMB open publicly to the internet you may see a suite of these logs on your server's event viewer. Although these are showing up as Event ID 4624 (which generally correlates to successful logon events), these are NOT successful access to the system without a correlating Event ID 4624 showing up with an Account Name \\domain\username and a type 10 logon code for RDP or a type 3 for SMB. You can double check this by looking at 4625 events for a failure, within a similar time range to the logon event for confirmation.

The reason for this is because when a user initiates an RDP or SMB connection, the con…