It sound like an interesting question, isn't it? But what I'm referring to is us analyst that searches for unusual activity or you just wait for a trigger from an IDS/IPS or that a rule will trigger something from the SIEM.

I watched the opening keynote by Amit Yoran President of RSA at the RSA Singapore conference [1] and he was made reference to large organizations who have cutting edge security software/hardware and how bad they are still failing at catching bad actors still go undetected for a long time. He shared five points to go by to help catch bad actors in a network: Does it really Help (this shiny new device or software), Visibility, Identity, Intelligence and Prioritize. The fourth point Intelligence is where he talks about "CISO that gives their security team the time to hunt and learn their environment to understand what normal looks like are much more rapidly identifying unusual patterns (23:53m)"[1]

I do go "hunting" looking for unusual activity and pattern IDS/IPS or even the SIEM doesn't know about. There is a lot of threat intelligence out there that can be used to detect unusual pattern of activity. Maybe you have a security device that use some form of feeds to detect bad actors (i.e. some vendors use DShield feeds), reviewing what they trigger might yield interesting data. How about taking the time to review if the systems communicating with the HR server(s) are part of the allowed list? This example could be added to a SIEM to trigger for unusual activity.

If you are a “hunter”, what do you look for?

[1] http://www.rsaconference.com/media/the-game-has-changed?

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Guy Bruneau IPSS Inc. gbruneau at isc dot sans dot edu