Splunk Enterprise Security
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How to identify which host the user is trying to access by using windows DC log.

Communicator

This question may not 100% related with Splunk but I am sure Splunker had done this many times so I thought I will just ask

I want to identify the real destination when user logon a host using authenticate through DC like Kerobers or NTLM. I looked at event 4624, 4768,4771 on the DC log, they only have real src information, but I cant find the real dest information in these event. Is there another event I should look at or it is some field is missing on these events? my example as below

user A using host A to logon to host C by go through DC B. and I only collect log at DC B, so I want to know how to identify the host C information from the log in this scenario.

Thank you in advanced.

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Re: How to identify which host the user is trying to access by using windows DC log.

Contributor

This might be possible with NTLM authentication, but Kerberos doesn't work that way.

With Kerberos, user A interacts with DC B from host A, then proceeds directly to host C with its service ticket in hand for the service(s) running on host C.

Under NTLM, host C will challenge user A to authenticate, which host C might verify with DC B (it very well could be some other domain controller). I think only with NTLM will you possibly see host C authenticating user A on DC B, but only if host C uses DC B...

Check this page for a decent graphic on how NTLM works:
https://medium.com/@m8r0wn/internal-information-disclosure-using-hidden-ntlm-authentication-18de1767...

And this page for how Kerberos works:
https://www.manageengine.com/products/active-directory-audit/kb/windows-security-log-event-id-4768.h...

I think the only way to make sure you capture this would be to turn on security auditing/logging on host C.

Hope that helps!
rmmiller

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