The rational approach to pretty much any IT project is the same…define the requirements, solutions, do a pilot project, implement/refine and operationalize.
Often you win or lose early at requirements gathering time.
So what should you keep in mind while defining requirements for a Security Information and Event Management (SIEM) project?
Look at it in two ways:
- What are the trends that you (and your peers) have seen and experienced?
- What are the experts saying?
Well, for ourselves, we see a clear increase in attacks from the outside. These are increasingly sophisticated (which is expected I guess since it’s an arms race) and disturbingly indiscriminate. Attacks seem to be launched merely because we exist on the Internet and have connectivity and disconnecting from the Internet is not an option.
We see attacks that we recognize immediately (100 login failures between 2-3 AM). We see attacks that are not so obvious (http traffic from a server that should not have any). And we see the almost unrecognizable zero-day attacks. These appear to work their way through our defenses and manifest as subtle configuration changes.
Of the expert prognosticators, we (like many others) find that the PCI-DSS standard is a good middle ground between loosely defined guidelines (HIPAA anyone?) and vendor “Best Practices”.
The interesting thing is that PCI-DSS requirements seem to match what we see. Section 10 speaks to weaponry that can detect (and ideally remediate) the attacks and Section 11.5 speaks to the ability to detect configuration changes.
Its all SIEM, in the end.
So what are the requirements for SIEM?
- Gather logs from a variety of sources in real-time
- The ability to detect (and ideally remediate) well recognized attacks in real-time
- The ability (and more importantly habit) to extract value from raw logs for the non-obvious attacks
- The ability to detect configuration changes to the file and registry level for those zero-day attacks
As the saying goes — well begun is half done. Get your requirements correct and improve your odds of success.