Security Correlation Then and Now: A Sad Truth About SIEM
We all know David Bianco Pyramid of Pain, a classic from 2013. The focus of this famous visual is on indicators that you “latch onto” in your detection activities. This post will reveal a related mystery connected to SIEM detection evolution and its current state. So, yeah, this is another way of saying that a very small number of people are perhaps very passionate about it …
But who am I kidding? I plan to present a dangerously long rant about the state of detection content today. So, yes, of course there will be jokes, but ultimately that is a serious thing that had been profoundly bothering me lately.
First, let’s travel to 1999 for a brief minute. Host IDS is very much a thing (but the phrase “something is a thing” has not yet been born), the term “SIEM” is barely a twinkle in a Gartner analyst eye. However, some vendors are starting to develop and sell “SIM” and “SEM” appliances (It is 1999! Appliances are HOT!).
Some of the first soon-to-be-called-SIEM tools have very basic “correlation” rules (really, just aggregation and counting of a single attribute like username or source IP) and have rules like “many connections to the same port across many destinations”, “Cisco PIX log message containing SYNflood, repeated 50 times” and “SSH login failure.” Most of these rules are very fragile i.e. a tiny deviation in attacker activities will cause it to not trigger. They are also very device dependent (i.e. you need to write such rules for every firewall device, for example). So the SIM / SEM vendor had to load up many hundreds of these rules. And customers had to suffer through enabling/disabling and tuning them. Yuck!
While we are still in 1999, a host IDS like say Dragon Squire, a true wonder of 1990s security technology, scoured logs for things like “FTP:NESSUS-PROBE” and “FTP:USER-NULL-REFUSED.” For this post, I reached deep into my log archives and actually reviewed some ancient (2002) Dragon HIDS logs to refresh my memory, and got into the vibe of that period (no, I didn’t do it on a Blackberry or using Crystal Reports — I am not that dedicated).
Now fast forward to about 2003–2004 — and the revolution happened! SIEM products unleashed normalized events and event taxonomies. I spent some of that time categorizing device event IDs (where does Windows Event ID 1102 go?) into SIEM taxonomy event types, and then writing detection rules on them. SIEM detection content writing became…