Friday, September 25, 2009
I was happy to find Anton Chuvakin's post about the issues of doing security based on risk management a few days ago. As I said on my twitter, "discussions about decision making (risk based vs. others) is the only thing interesting for me today on the security field". Anton made a very good summary about why we should consider alternatives to risk management and who else is talking about it.Honestly, I remember when I first read that 2006 article from Donn Parker that I was somewhat disapointed by his suggestion of doing things based on compliance. It was the old security sin "checklist based security". All the recent discussions about PCI DSS are great sources of opinions and insights about the subject, and I'm seeing that there's an overall perception from the security industry that it end up being good for security. Is the checklist based security working?If PCI DSS is working, it's certainly not because of those approaching it with a checklist based mind. It is because it is a quite good prescriptive standard. It is clear about what the organizations need to do. But is has limitations.PCI DSS has a very clear goal, to protect card and cardholder data. The standard allows a quick and dirty approach for those that don't want to bother with all those requirements. Reducing scope. Think about all those requirements about wireless networks. You have two choices, doing everything required by the standard or removing that network from the scope. With PCI, as long as you can prove that the cardholder data environment is protected, the rest can be hell, it doesn't matter, you are good to go. Is it wrong? Well, the standard has a clear goal and it makes sense to define the scope around it, but it is kind of naive on assuming that it's possible to isolate network environments inside the same organization without considering that the payment process (that uses card data) is usually very close to other core business processes. So, PCI DSS is a good standard but it is limited for overall information security purposes.With this in mind, one could say that creating a "generic PCI DSS" would be the solution for risk-less security. I think it is part of the solution, for sure. The problem is that the scope for that standard is considerably bigger, in a way that it would have to include some less prescriptive requirements. Is there a way of doing that without creating a new ISO27002? Don't get me wrong, I think ISO27002 is a great standard, but it is so open to interpretation that it can almost any beast can become a certified ISMS. Also, it has on its base the risk management process, that is exactly what we are trying to avoid. The new standard would have to include requirements to solve one of the biggest challenges on information security: prioritization.Prioritization is the achilles heel of any attempt of doing security without risk management. After all, everybody knows that we cannot protect everything and during the long implementation phases the bigger pains need to be addressed first. How can we do that without using that wizardry to "guess-timate risks"?My take is that it should be done based on two sources of information: benchmarking and threat modeling. Threat models can be generated based on geographic aspects, organization and business profiles, technology in use. Threats for banks in the same context (same country, for example) are probably very similar. Organizations using the same basic software package on its workstations will share the same threats for that technology too. We should also consider that a lot of the current threats organizations face are pervasive and ubiquotous, they affect almost any organization out there. Except for very few cases, malware issues are a common problem. Sure, the impact from malware issues will be different for each organization, but it seems to me that those characteristics will probably be those considered for many other threats too. How would an organization "risk-less" work to define its security strategy and the controls to implement? Most important, how it would check its own security status? Is it ok? Should it spend more? What needs to be improved?That's where the fun is. And no, I don't have those answers. But building the processes and tools to do that is definitely the most cool thing to do on this field.
Posted by Augusto Barros at 5:43 AM